diff --git a/mozilla/layout/html/table/src/BasicTableLayoutStrategy.cpp b/mozilla/layout/html/table/src/BasicTableLayoutStrategy.cpp
index bfbfb36a841..8c386257bb2 100644
--- a/mozilla/layout/html/table/src/BasicTableLayoutStrategy.cpp
+++ b/mozilla/layout/html/table/src/BasicTableLayoutStrategy.cpp
@@ -253,6 +253,7 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
   if (gsDebug==PR_TRUE) printf ("** %p: AssignPreliminaryColumnWidths **\n", mTableFrame);
   nsVoidArray *spanList=nsnull;
   nsVoidArray *colSpanList=nsnull;
+  PRInt32 numProvisionalFixedColumns = 0; // used for assigning width from cell with colspan to columns that are spanned
 
   PRBool hasColsAttribute = (PRBool)(NS_STYLE_TABLE_COLS_NONE!=mCols);
   
@@ -291,6 +292,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
     {
       haveColWidth = PR_TRUE;
       specifiedFixedColWidth = colPosition->mWidth.GetCoordValue();
+      if (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN==colFrame->GetWidthSource())
+        numProvisionalFixedColumns++;
     }
 
     /* Scan the column, simulatneously assigning column widths
@@ -341,7 +344,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
                 rowIndex, colSpan, cellMinSize.width, cellMinSize.height,
                 cellDesiredSize.width, cellDesiredSize.height);
 
-      if (PR_TRUE==haveColWidth)//  &&  PR_TRUE==cellGrantingWidth) 
+      if ((PR_TRUE==haveColWidth) && 
+          (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN!=colFrame->GetWidthSource()))
       {
         // This col has a specified fixed width so set the min and max width to the larger of 
         // (specified width, largest max_element_size of the cells in the column)
@@ -380,16 +384,6 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
           effectiveMinColumnWidth = cellMinWidth;
       }
 
-      //bookkeeping:  is this the cell that gave the column it's fixed width attribute?
-      // must be done after "haveColWidth && cellGrantingWidth" used above
-      if (PR_TRUE==cellGrantingWidth  && 1==colSpan)
-      {
-        const nsStylePosition* cellPosition;
-        cellFrame->GetStyleData(eStyleStruct_Position, (const nsStyleStruct *&)cellPosition);
-        if (eStyleUnit_Coord == cellPosition->mWidth.GetUnit())
-          cellGrantingWidth=PR_FALSE; //I've found the cell that gave the col it's width
-      }        
-
       if (1<colSpan)
       {
         // add the column to our list of post-process columns, if all of the intersected columns are auto
@@ -404,7 +398,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
             mTableFrame->GetColumnFrame(i+colIndex, cf);
             const nsStylePosition* colPos;
             cf->GetStyleData(eStyleStruct_Position, (nsStyleStruct*&)colPos);
-            if (colPos->mWidth.GetUnit() != eStyleUnit_Auto)
+            if (colPos->mWidth.GetUnit() != eStyleUnit_Auto &&
+               (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN!=cf->GetWidthSource()))
             {
               okToAdd = PR_FALSE;
               break;
@@ -412,20 +407,39 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
           }
         }
 
+        nscoord width = cellDesiredSize.width;  // used below as the cell's "natural" width
+        if (PR_TRUE == haveColWidth)
+          width = colSpan*specifiedFixedColWidth;
+
         if (PR_TRUE==okToAdd)
         {
-          ColSpanStruct *colSpanInfo = new ColSpanStruct(colSpan, colIndex, cellDesiredSize.width);
+          ColSpanStruct *colSpanInfo = new ColSpanStruct(colSpan, colIndex, width);
           if (nsnull==colSpanList)
             colSpanList = new nsVoidArray();
           colSpanList->AppendElement(colSpanInfo);
         }
 
-        // add the cell to our list of spanning cells
-        SpanInfo *spanInfo = new SpanInfo(colIndex, colSpan, cellMinWidth, cellDesiredWidth);
-        if (nsnull==spanList)
-          spanList = new nsVoidArray();
-        spanList->AppendElement(spanInfo);
+        if (PR_TRUE==cellGrantingWidth)
+        {
+          // add the cell to our list of spanning cells
+          SpanInfo *spanInfo = new SpanInfo(colIndex, colSpan, cellMinWidth, width);
+          if (nsnull==spanList)
+            spanList = new nsVoidArray();
+          spanList->AppendElement(spanInfo);
+        }
       }
+
+      //bookkeeping:  is this the cell that gave the column it's fixed width attribute?
+      // must be done after "haveColWidth && cellGrantingWidth" used above
+      if (PR_TRUE==cellGrantingWidth)
+      {
+        const nsStylePosition* cellPosition;
+        cellFrame->GetStyleData(eStyleStruct_Position, (const nsStyleStruct *&)cellPosition);
+        if (eStyleUnit_Coord == cellPosition->mWidth.GetUnit())
+          cellGrantingWidth=PR_FALSE; //I've found the cell that gave the col it's width
+      } 
+
+      // book 'em, Danno
       if (gsDebug) {
         printf ("    after cell %d, minColWidth = %d and maxColWidth = %d\n",
                 rowIndex, minColWidth, maxColWidth);
@@ -454,7 +468,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
     colFrame->SetEffectiveMaxColWidth(effectiveMaxColumnWidth);
     // this is the default, the real adjustment happens below where we deal with colspans
     colFrame->SetAdjustedMinColWidth(effectiveMinColumnWidth);  
-    if (PR_TRUE==haveColWidth)
+    if ((PR_TRUE==haveColWidth) && 
+        (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN!=colFrame->GetWidthSource()))
       mTableFrame->SetColumnWidth(colIndex, specifiedFixedColWidth);
     else
       mTableFrame->SetColumnWidth(colIndex, effectiveMaxColumnWidth);
@@ -467,8 +482,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
       maxColWidthArray[colIndex] = maxColWidth;
     }
     if (gsDebug==PR_TRUE) 
-      printf ("after col %d, minColWidth=%d effectiveMinColumnWidth=%d\n\tminTableWidth = %d and maxTableWidth = %d\n", 
-              colIndex, minColWidth, effectiveMinColumnWidth, mMinTableWidth, mMaxTableWidth);
+      printf ("after col %d, minColWidth=%d effectiveMinColumnWidth=%d\n\teffectiveMaxColumnWidth = %d\n", 
+              colIndex, minColWidth, effectiveMinColumnWidth, effectiveMaxColumnWidth);
   }
 
   // now, post-process the computed values based on the table attributes
@@ -479,10 +494,11 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
   if (nsnull!=spanList)
   {
     // we only want to do this if there are auto-cells involved
+    // or if we have columns that are provisionally fixed-width with colspans
     PRInt32 numAutoColumns=0;
     PRInt32 *autoColumns=nsnull;
     mTableFrame->GetColumnsByType(eStyleUnit_Auto, numAutoColumns, autoColumns);
-    if (0==numAutoColumns)
+    if (0==numAutoColumns && 0==numProvisionalFixedColumns)
     { //table fully specified, so no need to do any extra work here
       PRInt32 spanCount = spanList->Count();
       // go through the list backwards so we can delete easily
@@ -494,21 +510,21 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
       }
     }
     else
-    {
+    { // for every column, handle spanning cells that impact that column
       for (PRInt32 colIndex=0; colIndex<mNumCols; colIndex++)
       {
         if (gsDebug) printf("handling span for %d\n", colIndex);
         PRInt32 spanCount = spanList->Count();
         // go through the list backwards so we can delete easily
         for (PRInt32 spanIndex=spanCount-1; 0<=spanIndex; spanIndex--)
-        {
+        { // get each spanInfo struct and see if it impacts this column
           SpanInfo *spanInfo = (SpanInfo *)(spanList->ElementAt(spanIndex));
           // if the spanInfo is about a column before the current column, it effects 
           // the current column (otherwise it would have already been deleted.)
           if (spanInfo->initialColIndex <= colIndex)
           {
             if (0==spanInfo->effectiveMaxWidthOfSpannedCols)
-            {
+            { // if we have not yet computed effectiveMaxWidthOfSpannedCols, do it now
               for (PRInt32 span=0; span<spanInfo->initialColSpan; span++)
               {
                 nsTableColFrame *nextColFrame = mTableFrame->GetColFrame(colIndex+span);
@@ -550,10 +566,13 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
             nscoord spanCellMaxWidth;
             if (0!=spanInfo->effectiveMaxWidthOfSpannedCols)
             {
-              spanCellMaxWidth = (spanInfo->cellDesiredWidth * colFrame->GetEffectiveMaxColWidth()) /
-                                 (spanInfo->effectiveMaxWidthOfSpannedCols);
+              float percent = ((float)(colFrame->GetEffectiveMaxColWidth())) /
+                                 ((float)(spanInfo->effectiveMaxWidthOfSpannedCols));
+              spanCellMaxWidth = (nscoord)(((float)(spanInfo->cellDesiredWidth)) * percent);
               if (gsDebug==PR_TRUE) 
-                printf ("spanCellMaxWidth portion = %d\n", spanCellMaxWidth);
+                printf ("spanCellMaxWidth portion = %d with percent = %f from effMaxColW=%d and sum=%d\n", 
+                        spanCellMaxWidth, percent, colFrame->GetEffectiveMaxColWidth(),
+                        spanInfo->effectiveMaxWidthOfSpannedCols);
               if (colMaxWidth < spanCellMaxWidth)
               {
                 // make sure we're at least as big as our min
@@ -1561,7 +1580,7 @@ void BasicTableLayoutStrategy::DistributeExcessSpace(nscoord  aAvailWidth,
       nscoord excessForThisColumn = (nscoord)(excess*percent);
       nscoord colWidth = excessForThisColumn+oldColWidth;
       if (gsDebug==PR_TRUE) 
-        printf("  distribute excess to all columns:  column %d was %d, now set to %d from % = %f\n", 
+        printf("  distribute excess: column %d was %d, now %d from %=%f\n", 
                colIndex, oldColWidth, colWidth, percent);
       mTableFrame->SetColumnWidth(colIndex, colWidth);
     }
diff --git a/mozilla/layout/html/table/src/nsCellMap.cpp b/mozilla/layout/html/table/src/nsCellMap.cpp
index befaa3ddb40..daba16d32b5 100644
--- a/mozilla/layout/html/table/src/nsCellMap.cpp
+++ b/mozilla/layout/html/table/src/nsCellMap.cpp
@@ -35,6 +35,7 @@ nsCellMap::nsCellMap(int aRows, int aColumns)
 {
   mCells = nsnull;
   mColFrames = nsnull;
+  mMinColSpans = nsnull;
   Reset(aRows, aColumns);
 }
 
@@ -57,10 +58,13 @@ nsCellMap::~nsCellMap()
     }
     delete [] mCells;
   }
-  if (nsnull!= mColFrames)
+  if (nsnull != mColFrames)
     delete mColFrames;
+  if (nsnull != mMinColSpans)
+    delete [] mMinColSpans;
   mCells = nsnull;
   mColFrames = nsnull;
+  mMinColSpans = nsnull;
 };
 
 
@@ -131,5 +135,32 @@ nsTableColFrame* nsCellMap::GetColumnFrame(PRInt32 aColIndex)
 }
 
 
+void nsCellMap::SetMinColSpan(PRInt32 aColIndex, PRBool aColSpan)
+{
+  NS_ASSERTION(aColIndex<mColCount, "bad aColIndex");
+  NS_ASSERTION(aColSpan>=0, "bad aColSpan");
+
+  // initialize the data structure if not already done
+  if (nsnull==mMinColSpans)
+  {
+    mMinColSpans = new PRInt32[mColCount];
+    for (PRInt32 i=0; i<mColCount; i++)
+      mMinColSpans[i]=1;
+  }
+
+  mMinColSpans[aColIndex] = aColSpan;
+}
+
+PRInt32 nsCellMap::GetMinColSpan(PRInt32 aColIndex)
+{
+  NS_ASSERTION(aColIndex<mColCount, "bad aColIndex");
+
+  PRInt32 result = 1; // default is 1, mMinColSpans need not be allocated for tables with no spans
+  if (nsnull!=mMinColSpans)
+    result = mMinColSpans[aColIndex];
+  return result;
+}
+
+
 
 
diff --git a/mozilla/layout/html/table/src/nsCellMap.h b/mozilla/layout/html/table/src/nsCellMap.h
index 72961a4643a..54dfdc51f0c 100644
--- a/mozilla/layout/html/table/src/nsCellMap.h
+++ b/mozilla/layout/html/table/src/nsCellMap.h
@@ -43,6 +43,9 @@ protected:
   /** storage for CellData pointers */
   PRInt32 *mCells;       ///XXX CellData *?
 
+  /** storage for CellData pointers */
+  PRInt32 *mMinColSpans;
+
   /** a cache of the column frames, by col index */
   nsVoidArray * mColFrames;
 
@@ -81,6 +84,9 @@ public:
 
   nsTableColFrame * GetColumnFrame(PRInt32 aColIndex);
 
+  void    SetMinColSpan(PRInt32 aColIndex, PRBool  aColSpan);
+  PRInt32 GetMinColSpan(PRInt32 aColIndex);
+
   void AppendColumnFrame(nsTableColFrame *aColFrame);
 
   PRBool RowImpactedBySpanningCell(PRInt32 aRowIndex);
diff --git a/mozilla/layout/html/table/src/nsTableFrame.cpp b/mozilla/layout/html/table/src/nsTableFrame.cpp
index bb3c77be06f..a4607729bf7 100644
--- a/mozilla/layout/html/table/src/nsTableFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableFrame.cpp
@@ -469,13 +469,24 @@ PRInt32 nsTableFrame::GetEffectiveColSpan (PRInt32 aColIndex, nsTableCellFrame *
   NS_PRECONDITION (nsnull!=cellMap, "bad call, cellMap not yet allocated.");
   NS_PRECONDITION (0<=aColIndex && aColIndex<GetColCount(), "bad col index arg");
 
+  PRInt32 result;
   if (cellMap->GetRowCount()==1)
     return 1;
   PRInt32 colSpan = aCell->GetColSpan();
   PRInt32 colCount = GetColCount();
   if (colCount < (aColIndex + colSpan))
-    return (colCount - aColIndex);
-  return colSpan;
+    result =  colCount - aColIndex;
+  else
+  {
+    result = colSpan;
+    // check for case where all cells in a column have a colspan
+    PRInt32 initialColIndex = aCell->GetColIndex();
+    PRInt32 minColSpanForCol = cellMap->GetMinColSpan(initialColIndex);
+    result -= (minColSpanForCol - 1); // minColSpanForCol is always at least 1
+                                      // and we want to treat default as 0 (no effect)
+  }
+
+  return result;
 }
 
 PRInt32 nsTableFrame::GetEffectiveCOLSAttribute()
@@ -691,8 +702,6 @@ void nsTableFrame::BuildCellMap ()
       PRInt32 colIndex = 0;
       nsIFrame* cellFrame;
       rowFrame->FirstChild(cellFrame);
-      if (gsDebug==PR_TRUE) 
-        DumpCellMap();
 
       while ((nsnull != cellFrame) && (colIndex < mColCount))
       {
@@ -745,6 +754,26 @@ void nsTableFrame::BuildCellMap ()
   }
   if (gsDebug==PR_TRUE)
     DumpCellMap ();
+  // iterate through the columns setting the min col span if necessary
+  // it would be more efficient if we could do this in the above loop
+  for (PRInt32 colIndex=0; colIndex<mColCount; colIndex++)
+  {
+    PRInt32 minColSpan;
+    for (PRInt32 rowIndex=0; rowIndex<rowCount; rowIndex++)
+    {
+      nsTableCellFrame *cellFrame = mCellMap->GetCellFrameAt(rowIndex, colIndex);
+      if (nsnull!=cellFrame)
+      {
+        PRInt32 colSpan = cellFrame->GetColSpan();
+        if (0==rowIndex)
+          minColSpan = colSpan;
+        else
+          minColSpan = PR_MIN(minColSpan, colSpan);
+      }
+    }
+    if (1!=minColSpan)
+      mCellMap->SetMinColSpan(colIndex, minColSpan);
+  }
 }
 
 /**
@@ -2529,27 +2558,31 @@ nsTableFrame::SetColumnStyleFromCell(nsIPresContext  * aPresContext,
         GetColumnFrame(i+aCellFrame->GetColIndex(), colFrame);
         if (nsTableColFrame::eWIDTH_SOURCE_CELL != colFrame->GetWidthSource()) 
         {
-          // get the column style and set the width attribute
-          nsIStyleContext *colSC;
-          colFrame->GetStyleContext(aPresContext, colSC);
-          nsStylePosition* colPosition = (nsStylePosition*) colSC->GetMutableStyleData(eStyleStruct_Position);
-          NS_RELEASE(colSC);
-          // set the column width attribute
-          if (eStyleUnit_Coord == cellPosition->mWidth.GetUnit())
+          if ((1==colSpan) ||
+              (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN != colFrame->GetWidthSource()))
           {
-            nscoord width = cellPosition->mWidth.GetCoordValue();
-            colPosition->mWidth.SetCoordValue(width/colSpan);
+            // get the column style and set the width attribute
+            nsIStyleContext *colSC;
+            colFrame->GetStyleContext(aPresContext, colSC);
+            nsStylePosition* colPosition = (nsStylePosition*) colSC->GetMutableStyleData(eStyleStruct_Position);
+            NS_RELEASE(colSC);
+            // set the column width attribute
+            if (eStyleUnit_Coord == cellPosition->mWidth.GetUnit())
+            {
+              nscoord width = cellPosition->mWidth.GetCoordValue();
+              colPosition->mWidth.SetCoordValue(width/colSpan);
+            }
+            else
+            {
+              float width = cellPosition->mWidth.GetPercentValue();
+              colPosition->mWidth.SetPercentValue(width/colSpan);
+            }
+            // set the column width-set-type
+            if (1==colSpan)
+              colFrame->SetWidthSource(nsTableColFrame::eWIDTH_SOURCE_CELL);
+            else
+              colFrame->SetWidthSource(nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN);
           }
-          else
-          {
-            float width = cellPosition->mWidth.GetPercentValue();
-            colPosition->mWidth.SetPercentValue(width/colSpan);
-          }
-          // set the column width-set-type
-          if (1==colSpan)
-            colFrame->SetWidthSource(nsTableColFrame::eWIDTH_SOURCE_CELL);
-          else
-            colFrame->SetWidthSource(nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN);
         }
       }
     }
diff --git a/mozilla/layout/tables/BasicTableLayoutStrategy.cpp b/mozilla/layout/tables/BasicTableLayoutStrategy.cpp
index bfbfb36a841..8c386257bb2 100644
--- a/mozilla/layout/tables/BasicTableLayoutStrategy.cpp
+++ b/mozilla/layout/tables/BasicTableLayoutStrategy.cpp
@@ -253,6 +253,7 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
   if (gsDebug==PR_TRUE) printf ("** %p: AssignPreliminaryColumnWidths **\n", mTableFrame);
   nsVoidArray *spanList=nsnull;
   nsVoidArray *colSpanList=nsnull;
+  PRInt32 numProvisionalFixedColumns = 0; // used for assigning width from cell with colspan to columns that are spanned
 
   PRBool hasColsAttribute = (PRBool)(NS_STYLE_TABLE_COLS_NONE!=mCols);
   
@@ -291,6 +292,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
     {
       haveColWidth = PR_TRUE;
       specifiedFixedColWidth = colPosition->mWidth.GetCoordValue();
+      if (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN==colFrame->GetWidthSource())
+        numProvisionalFixedColumns++;
     }
 
     /* Scan the column, simulatneously assigning column widths
@@ -341,7 +344,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
                 rowIndex, colSpan, cellMinSize.width, cellMinSize.height,
                 cellDesiredSize.width, cellDesiredSize.height);
 
-      if (PR_TRUE==haveColWidth)//  &&  PR_TRUE==cellGrantingWidth) 
+      if ((PR_TRUE==haveColWidth) && 
+          (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN!=colFrame->GetWidthSource()))
       {
         // This col has a specified fixed width so set the min and max width to the larger of 
         // (specified width, largest max_element_size of the cells in the column)
@@ -380,16 +384,6 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
           effectiveMinColumnWidth = cellMinWidth;
       }
 
-      //bookkeeping:  is this the cell that gave the column it's fixed width attribute?
-      // must be done after "haveColWidth && cellGrantingWidth" used above
-      if (PR_TRUE==cellGrantingWidth  && 1==colSpan)
-      {
-        const nsStylePosition* cellPosition;
-        cellFrame->GetStyleData(eStyleStruct_Position, (const nsStyleStruct *&)cellPosition);
-        if (eStyleUnit_Coord == cellPosition->mWidth.GetUnit())
-          cellGrantingWidth=PR_FALSE; //I've found the cell that gave the col it's width
-      }        
-
       if (1<colSpan)
       {
         // add the column to our list of post-process columns, if all of the intersected columns are auto
@@ -404,7 +398,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
             mTableFrame->GetColumnFrame(i+colIndex, cf);
             const nsStylePosition* colPos;
             cf->GetStyleData(eStyleStruct_Position, (nsStyleStruct*&)colPos);
-            if (colPos->mWidth.GetUnit() != eStyleUnit_Auto)
+            if (colPos->mWidth.GetUnit() != eStyleUnit_Auto &&
+               (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN!=cf->GetWidthSource()))
             {
               okToAdd = PR_FALSE;
               break;
@@ -412,20 +407,39 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
           }
         }
 
+        nscoord width = cellDesiredSize.width;  // used below as the cell's "natural" width
+        if (PR_TRUE == haveColWidth)
+          width = colSpan*specifiedFixedColWidth;
+
         if (PR_TRUE==okToAdd)
         {
-          ColSpanStruct *colSpanInfo = new ColSpanStruct(colSpan, colIndex, cellDesiredSize.width);
+          ColSpanStruct *colSpanInfo = new ColSpanStruct(colSpan, colIndex, width);
           if (nsnull==colSpanList)
             colSpanList = new nsVoidArray();
           colSpanList->AppendElement(colSpanInfo);
         }
 
-        // add the cell to our list of spanning cells
-        SpanInfo *spanInfo = new SpanInfo(colIndex, colSpan, cellMinWidth, cellDesiredWidth);
-        if (nsnull==spanList)
-          spanList = new nsVoidArray();
-        spanList->AppendElement(spanInfo);
+        if (PR_TRUE==cellGrantingWidth)
+        {
+          // add the cell to our list of spanning cells
+          SpanInfo *spanInfo = new SpanInfo(colIndex, colSpan, cellMinWidth, width);
+          if (nsnull==spanList)
+            spanList = new nsVoidArray();
+          spanList->AppendElement(spanInfo);
+        }
       }
+
+      //bookkeeping:  is this the cell that gave the column it's fixed width attribute?
+      // must be done after "haveColWidth && cellGrantingWidth" used above
+      if (PR_TRUE==cellGrantingWidth)
+      {
+        const nsStylePosition* cellPosition;
+        cellFrame->GetStyleData(eStyleStruct_Position, (const nsStyleStruct *&)cellPosition);
+        if (eStyleUnit_Coord == cellPosition->mWidth.GetUnit())
+          cellGrantingWidth=PR_FALSE; //I've found the cell that gave the col it's width
+      } 
+
+      // book 'em, Danno
       if (gsDebug) {
         printf ("    after cell %d, minColWidth = %d and maxColWidth = %d\n",
                 rowIndex, minColWidth, maxColWidth);
@@ -454,7 +468,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
     colFrame->SetEffectiveMaxColWidth(effectiveMaxColumnWidth);
     // this is the default, the real adjustment happens below where we deal with colspans
     colFrame->SetAdjustedMinColWidth(effectiveMinColumnWidth);  
-    if (PR_TRUE==haveColWidth)
+    if ((PR_TRUE==haveColWidth) && 
+        (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN!=colFrame->GetWidthSource()))
       mTableFrame->SetColumnWidth(colIndex, specifiedFixedColWidth);
     else
       mTableFrame->SetColumnWidth(colIndex, effectiveMaxColumnWidth);
@@ -467,8 +482,8 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
       maxColWidthArray[colIndex] = maxColWidth;
     }
     if (gsDebug==PR_TRUE) 
-      printf ("after col %d, minColWidth=%d effectiveMinColumnWidth=%d\n\tminTableWidth = %d and maxTableWidth = %d\n", 
-              colIndex, minColWidth, effectiveMinColumnWidth, mMinTableWidth, mMaxTableWidth);
+      printf ("after col %d, minColWidth=%d effectiveMinColumnWidth=%d\n\teffectiveMaxColumnWidth = %d\n", 
+              colIndex, minColWidth, effectiveMinColumnWidth, effectiveMaxColumnWidth);
   }
 
   // now, post-process the computed values based on the table attributes
@@ -479,10 +494,11 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
   if (nsnull!=spanList)
   {
     // we only want to do this if there are auto-cells involved
+    // or if we have columns that are provisionally fixed-width with colspans
     PRInt32 numAutoColumns=0;
     PRInt32 *autoColumns=nsnull;
     mTableFrame->GetColumnsByType(eStyleUnit_Auto, numAutoColumns, autoColumns);
-    if (0==numAutoColumns)
+    if (0==numAutoColumns && 0==numProvisionalFixedColumns)
     { //table fully specified, so no need to do any extra work here
       PRInt32 spanCount = spanList->Count();
       // go through the list backwards so we can delete easily
@@ -494,21 +510,21 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
       }
     }
     else
-    {
+    { // for every column, handle spanning cells that impact that column
       for (PRInt32 colIndex=0; colIndex<mNumCols; colIndex++)
       {
         if (gsDebug) printf("handling span for %d\n", colIndex);
         PRInt32 spanCount = spanList->Count();
         // go through the list backwards so we can delete easily
         for (PRInt32 spanIndex=spanCount-1; 0<=spanIndex; spanIndex--)
-        {
+        { // get each spanInfo struct and see if it impacts this column
           SpanInfo *spanInfo = (SpanInfo *)(spanList->ElementAt(spanIndex));
           // if the spanInfo is about a column before the current column, it effects 
           // the current column (otherwise it would have already been deleted.)
           if (spanInfo->initialColIndex <= colIndex)
           {
             if (0==spanInfo->effectiveMaxWidthOfSpannedCols)
-            {
+            { // if we have not yet computed effectiveMaxWidthOfSpannedCols, do it now
               for (PRInt32 span=0; span<spanInfo->initialColSpan; span++)
               {
                 nsTableColFrame *nextColFrame = mTableFrame->GetColFrame(colIndex+span);
@@ -550,10 +566,13 @@ PRBool BasicTableLayoutStrategy::AssignPreliminaryColumnWidths()
             nscoord spanCellMaxWidth;
             if (0!=spanInfo->effectiveMaxWidthOfSpannedCols)
             {
-              spanCellMaxWidth = (spanInfo->cellDesiredWidth * colFrame->GetEffectiveMaxColWidth()) /
-                                 (spanInfo->effectiveMaxWidthOfSpannedCols);
+              float percent = ((float)(colFrame->GetEffectiveMaxColWidth())) /
+                                 ((float)(spanInfo->effectiveMaxWidthOfSpannedCols));
+              spanCellMaxWidth = (nscoord)(((float)(spanInfo->cellDesiredWidth)) * percent);
               if (gsDebug==PR_TRUE) 
-                printf ("spanCellMaxWidth portion = %d\n", spanCellMaxWidth);
+                printf ("spanCellMaxWidth portion = %d with percent = %f from effMaxColW=%d and sum=%d\n", 
+                        spanCellMaxWidth, percent, colFrame->GetEffectiveMaxColWidth(),
+                        spanInfo->effectiveMaxWidthOfSpannedCols);
               if (colMaxWidth < spanCellMaxWidth)
               {
                 // make sure we're at least as big as our min
@@ -1561,7 +1580,7 @@ void BasicTableLayoutStrategy::DistributeExcessSpace(nscoord  aAvailWidth,
       nscoord excessForThisColumn = (nscoord)(excess*percent);
       nscoord colWidth = excessForThisColumn+oldColWidth;
       if (gsDebug==PR_TRUE) 
-        printf("  distribute excess to all columns:  column %d was %d, now set to %d from % = %f\n", 
+        printf("  distribute excess: column %d was %d, now %d from %=%f\n", 
                colIndex, oldColWidth, colWidth, percent);
       mTableFrame->SetColumnWidth(colIndex, colWidth);
     }
diff --git a/mozilla/layout/tables/nsCellMap.cpp b/mozilla/layout/tables/nsCellMap.cpp
index befaa3ddb40..daba16d32b5 100644
--- a/mozilla/layout/tables/nsCellMap.cpp
+++ b/mozilla/layout/tables/nsCellMap.cpp
@@ -35,6 +35,7 @@ nsCellMap::nsCellMap(int aRows, int aColumns)
 {
   mCells = nsnull;
   mColFrames = nsnull;
+  mMinColSpans = nsnull;
   Reset(aRows, aColumns);
 }
 
@@ -57,10 +58,13 @@ nsCellMap::~nsCellMap()
     }
     delete [] mCells;
   }
-  if (nsnull!= mColFrames)
+  if (nsnull != mColFrames)
     delete mColFrames;
+  if (nsnull != mMinColSpans)
+    delete [] mMinColSpans;
   mCells = nsnull;
   mColFrames = nsnull;
+  mMinColSpans = nsnull;
 };
 
 
@@ -131,5 +135,32 @@ nsTableColFrame* nsCellMap::GetColumnFrame(PRInt32 aColIndex)
 }
 
 
+void nsCellMap::SetMinColSpan(PRInt32 aColIndex, PRBool aColSpan)
+{
+  NS_ASSERTION(aColIndex<mColCount, "bad aColIndex");
+  NS_ASSERTION(aColSpan>=0, "bad aColSpan");
+
+  // initialize the data structure if not already done
+  if (nsnull==mMinColSpans)
+  {
+    mMinColSpans = new PRInt32[mColCount];
+    for (PRInt32 i=0; i<mColCount; i++)
+      mMinColSpans[i]=1;
+  }
+
+  mMinColSpans[aColIndex] = aColSpan;
+}
+
+PRInt32 nsCellMap::GetMinColSpan(PRInt32 aColIndex)
+{
+  NS_ASSERTION(aColIndex<mColCount, "bad aColIndex");
+
+  PRInt32 result = 1; // default is 1, mMinColSpans need not be allocated for tables with no spans
+  if (nsnull!=mMinColSpans)
+    result = mMinColSpans[aColIndex];
+  return result;
+}
+
+
 
 
diff --git a/mozilla/layout/tables/nsCellMap.h b/mozilla/layout/tables/nsCellMap.h
index 72961a4643a..54dfdc51f0c 100644
--- a/mozilla/layout/tables/nsCellMap.h
+++ b/mozilla/layout/tables/nsCellMap.h
@@ -43,6 +43,9 @@ protected:
   /** storage for CellData pointers */
   PRInt32 *mCells;       ///XXX CellData *?
 
+  /** storage for CellData pointers */
+  PRInt32 *mMinColSpans;
+
   /** a cache of the column frames, by col index */
   nsVoidArray * mColFrames;
 
@@ -81,6 +84,9 @@ public:
 
   nsTableColFrame * GetColumnFrame(PRInt32 aColIndex);
 
+  void    SetMinColSpan(PRInt32 aColIndex, PRBool  aColSpan);
+  PRInt32 GetMinColSpan(PRInt32 aColIndex);
+
   void AppendColumnFrame(nsTableColFrame *aColFrame);
 
   PRBool RowImpactedBySpanningCell(PRInt32 aRowIndex);
diff --git a/mozilla/layout/tables/nsTableFrame.cpp b/mozilla/layout/tables/nsTableFrame.cpp
index bb3c77be06f..a4607729bf7 100644
--- a/mozilla/layout/tables/nsTableFrame.cpp
+++ b/mozilla/layout/tables/nsTableFrame.cpp
@@ -469,13 +469,24 @@ PRInt32 nsTableFrame::GetEffectiveColSpan (PRInt32 aColIndex, nsTableCellFrame *
   NS_PRECONDITION (nsnull!=cellMap, "bad call, cellMap not yet allocated.");
   NS_PRECONDITION (0<=aColIndex && aColIndex<GetColCount(), "bad col index arg");
 
+  PRInt32 result;
   if (cellMap->GetRowCount()==1)
     return 1;
   PRInt32 colSpan = aCell->GetColSpan();
   PRInt32 colCount = GetColCount();
   if (colCount < (aColIndex + colSpan))
-    return (colCount - aColIndex);
-  return colSpan;
+    result =  colCount - aColIndex;
+  else
+  {
+    result = colSpan;
+    // check for case where all cells in a column have a colspan
+    PRInt32 initialColIndex = aCell->GetColIndex();
+    PRInt32 minColSpanForCol = cellMap->GetMinColSpan(initialColIndex);
+    result -= (minColSpanForCol - 1); // minColSpanForCol is always at least 1
+                                      // and we want to treat default as 0 (no effect)
+  }
+
+  return result;
 }
 
 PRInt32 nsTableFrame::GetEffectiveCOLSAttribute()
@@ -691,8 +702,6 @@ void nsTableFrame::BuildCellMap ()
       PRInt32 colIndex = 0;
       nsIFrame* cellFrame;
       rowFrame->FirstChild(cellFrame);
-      if (gsDebug==PR_TRUE) 
-        DumpCellMap();
 
       while ((nsnull != cellFrame) && (colIndex < mColCount))
       {
@@ -745,6 +754,26 @@ void nsTableFrame::BuildCellMap ()
   }
   if (gsDebug==PR_TRUE)
     DumpCellMap ();
+  // iterate through the columns setting the min col span if necessary
+  // it would be more efficient if we could do this in the above loop
+  for (PRInt32 colIndex=0; colIndex<mColCount; colIndex++)
+  {
+    PRInt32 minColSpan;
+    for (PRInt32 rowIndex=0; rowIndex<rowCount; rowIndex++)
+    {
+      nsTableCellFrame *cellFrame = mCellMap->GetCellFrameAt(rowIndex, colIndex);
+      if (nsnull!=cellFrame)
+      {
+        PRInt32 colSpan = cellFrame->GetColSpan();
+        if (0==rowIndex)
+          minColSpan = colSpan;
+        else
+          minColSpan = PR_MIN(minColSpan, colSpan);
+      }
+    }
+    if (1!=minColSpan)
+      mCellMap->SetMinColSpan(colIndex, minColSpan);
+  }
 }
 
 /**
@@ -2529,27 +2558,31 @@ nsTableFrame::SetColumnStyleFromCell(nsIPresContext  * aPresContext,
         GetColumnFrame(i+aCellFrame->GetColIndex(), colFrame);
         if (nsTableColFrame::eWIDTH_SOURCE_CELL != colFrame->GetWidthSource()) 
         {
-          // get the column style and set the width attribute
-          nsIStyleContext *colSC;
-          colFrame->GetStyleContext(aPresContext, colSC);
-          nsStylePosition* colPosition = (nsStylePosition*) colSC->GetMutableStyleData(eStyleStruct_Position);
-          NS_RELEASE(colSC);
-          // set the column width attribute
-          if (eStyleUnit_Coord == cellPosition->mWidth.GetUnit())
+          if ((1==colSpan) ||
+              (nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN != colFrame->GetWidthSource()))
           {
-            nscoord width = cellPosition->mWidth.GetCoordValue();
-            colPosition->mWidth.SetCoordValue(width/colSpan);
+            // get the column style and set the width attribute
+            nsIStyleContext *colSC;
+            colFrame->GetStyleContext(aPresContext, colSC);
+            nsStylePosition* colPosition = (nsStylePosition*) colSC->GetMutableStyleData(eStyleStruct_Position);
+            NS_RELEASE(colSC);
+            // set the column width attribute
+            if (eStyleUnit_Coord == cellPosition->mWidth.GetUnit())
+            {
+              nscoord width = cellPosition->mWidth.GetCoordValue();
+              colPosition->mWidth.SetCoordValue(width/colSpan);
+            }
+            else
+            {
+              float width = cellPosition->mWidth.GetPercentValue();
+              colPosition->mWidth.SetPercentValue(width/colSpan);
+            }
+            // set the column width-set-type
+            if (1==colSpan)
+              colFrame->SetWidthSource(nsTableColFrame::eWIDTH_SOURCE_CELL);
+            else
+              colFrame->SetWidthSource(nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN);
           }
-          else
-          {
-            float width = cellPosition->mWidth.GetPercentValue();
-            colPosition->mWidth.SetPercentValue(width/colSpan);
-          }
-          // set the column width-set-type
-          if (1==colSpan)
-            colFrame->SetWidthSource(nsTableColFrame::eWIDTH_SOURCE_CELL);
-          else
-            colFrame->SetWidthSource(nsTableColFrame::eWIDTH_SOURCE_CELL_WITH_SPAN);
         }
       }
     }