diff --git a/mozilla/layout/html/table/src/nsCellMap.cpp b/mozilla/layout/html/table/src/nsCellMap.cpp
index 19f7652e730..077cd9b0154 100644
--- a/mozilla/layout/html/table/src/nsCellMap.cpp
+++ b/mozilla/layout/html/table/src/nsCellMap.cpp
@@ -478,7 +478,9 @@ nsTableCellMap::InsertRows(nsTableRowGroupFrame& aParent,
       cellMap->InsertRows(*this, aRows, rowIndex, aConsiderSpans, aDamageArea);
       aDamageArea.y = aFirstRowIndex;
       aDamageArea.height = PR_MAX(0, GetRowCount() - aFirstRowIndex);
-      //Dump("after InsertRows");
+#ifdef DEBUG_TABLE_CELLMAP 
+      Dump("after InsertRows");
+#endif
       if (mBCInfo) {
         BCData* bcData;
         PRInt32 count = mBCInfo->mRightBorders.Count();
@@ -536,7 +538,9 @@ nsTableCellMap::RemoveRows(PRInt32         aFirstRowIndex,
     rowIndex -= cellMap->GetRowCount();
     cellMap = cellMap->GetNextSibling();
   }
-  //Dump("after RemoveRows");
+#ifdef DEBUG_TABLE_CELLMAP
+  Dump("after RemoveRows");
+#endif
 }
 
 PRInt32
@@ -582,7 +586,9 @@ nsTableCellMap::AppendCell(nsTableCellFrame& aCellFrame,
     rowIndex -= cellMap->GetRowCount();
     cellMap = cellMap->GetNextSibling();
   }
-  //Dump("after AppendCell");
+#ifdef DEBUG_TABLE_CELLMAP
+  Dump("after AppendCell");
+#endif
   return result;
 }
 
@@ -606,7 +612,9 @@ nsTableCellMap::InsertCells(nsVoidArray&          aCellFrames,
     rowIndex -= cellMap->GetRowCount();
     cellMap = cellMap->GetNextSibling();
   }
-  //Dump("after InsertCells");
+#ifdef DEBUG_TABLE_CELLMAP
+  Dump("after InsertCells");
+#endif
 }
 
 
@@ -628,7 +636,9 @@ nsTableCellMap::RemoveCell(nsTableCellFrame* aCellFrame,
       PRInt32 colIndex;
       aCellFrame->GetColIndex(colIndex);
       aDamageArea.width = PR_MAX(0, GetColCount() - colIndex - 1);
-      //Dump("after RemoveCell");
+#ifdef DEBUG_TABLE_CELLMAP
+      Dump("after RemoveCell");
+#endif
       return;
     }
     rowIndex -= cellMap->GetRowCount();
@@ -1255,7 +1265,15 @@ nsCellMap::AppendCell(nsTableCellMap&   aMap,
 
   // Setup CellData for this cell
   if (origData) {
+    NS_ASSERTION(origData->IsDead(), "replacing a non dead cell is a memory leak");
     origData->Init(aCellFrame);
+    // we are replacing a dead cell, increase the number of cells 
+    // originating at this column
+    nsColInfo* colInfo = aMap.GetColInfoAt(startColIndex);
+    NS_ASSERTION(colInfo, "access to a non existing column");
+    if (colInfo) { 
+      colInfo->mNumCellsOrig++;
+    }
   }
   else {
     origData = (aMap.mBCInfo) ? new BCCellData(aCellFrame) : new CellData(aCellFrame); if (!origData) ABORT1(origData);
@@ -1331,8 +1349,10 @@ nsCellMap::AppendCell(nsTableCellMap&   aMap,
       }
     }
   }
-  //printf("appended cell=%p row=%d \n", aCellFrame, aRowIndex);
-  //aMap.Dump();
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("appended cell=%p row=%d \n", aCellFrame, aRowIndex);
+  aMap.Dump();
+#endif
   return origData;
 }
 
diff --git a/mozilla/layout/html/table/src/nsCellMap.h b/mozilla/layout/html/table/src/nsCellMap.h
index e337d74cbd0..e7696f89677 100644
--- a/mozilla/layout/html/table/src/nsCellMap.h
+++ b/mozilla/layout/html/table/src/nsCellMap.h
@@ -42,6 +42,8 @@
 #include "nsVoidArray.h"
 #include "nsRect.h"
 
+#undef DEBUG_TABLE_CELLMAP
+
 class nsTableColFrame;
 class nsTableCellFrame;
 class nsTableRowGroupFrame;
diff --git a/mozilla/layout/html/table/src/nsTableFrame.cpp b/mozilla/layout/html/table/src/nsTableFrame.cpp
index a656fbfda6c..6b9889f51c5 100644
--- a/mozilla/layout/html/table/src/nsTableFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableFrame.cpp
@@ -1121,8 +1121,10 @@ nsTableFrame::InsertRows(nsIPresContext&       aPresContext,
                          PRInt32               aRowIndex,
                          PRBool                aConsiderSpans)
 {
-  //printf("insertRowsBefore firstRow=%d \n", aRowIndex);
-  //Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("insertRowsBefore firstRow=%d \n", aRowIndex);
+  Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#endif
 
   PRInt32 numColsToAdd = 0;
   nsTableCellMap* cellMap = GetCellMap();
@@ -1152,9 +1154,10 @@ nsTableFrame::InsertRows(nsIPresContext&       aPresContext,
       SetBCDamageArea(aPresContext, damageArea);
     }
   }
-
-  //printf("insertRowsAfter \n");
-  //Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("insertRowsAfter \n");
+  Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#endif
 
   return numColsToAdd;
 }
@@ -1165,10 +1168,6 @@ void nsTableFrame::RemoveRows(nsIPresContext&  aPresContext,
                               PRInt32          aNumRowsToRemove,
                               PRBool           aConsiderSpans)
 {
-  //printf("removeRowsBefore firstRow=%d numRows=%d\n", aFirstRowIndex, aNumRowsToRemove);
-  //Dump(PR_TRUE, PR_FALSE, PR_TRUE);
-
-  
 #ifdef TBD_OPTIMIZATION
   // decide if we need to rebalance. we have to do this here because the row group 
   // cannot do it when it gets the dirty reflow corresponding to the frame being destroyed
@@ -1186,6 +1185,10 @@ void nsTableFrame::RemoveRows(nsIPresContext&  aPresContext,
 #endif
 
   PRInt32 firstRowIndex = aFirstRowFrame.GetRowIndex();
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("removeRowsBefore firstRow=%d numRows=%d\n", firstRowIndex, aNumRowsToRemove);
+  Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#endif
   nsTableCellMap* cellMap = GetCellMap();
   if (cellMap) {
     nsRect damageArea(0,0,0,0);
@@ -1207,8 +1210,10 @@ void nsTableFrame::RemoveRows(nsIPresContext&  aPresContext,
     }
   }
   AdjustRowIndices(firstRowIndex, -aNumRowsToRemove);
-  //printf("removeRowsAfter\n");
-  //Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("removeRowsAfter\n");
+  Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#endif
 }
 
 void nsTableFrame::AppendRowGroups(nsIPresContext& aPresContext,
@@ -6056,7 +6061,9 @@ nsTableFrame::CalcBCBorders(nsIPresContext& aPresContext)
   // reset the bc flag and damage area
   SetNeedToCalcBCBorders(PR_FALSE);
   propData->mDamageArea.x = propData->mDamageArea.y = propData->mDamageArea.width = propData->mDamageArea.height = 0;
-  //mCellMap->Dump();
+#ifdef DEBUG_TABLE_CELLMAP
+  mCellMap->Dump();
+#endif
 }
 
 // Iterates over borders (left border, corner, top border) in the cell map within a damage area
diff --git a/mozilla/layout/tables/nsCellMap.cpp b/mozilla/layout/tables/nsCellMap.cpp
index 19f7652e730..077cd9b0154 100644
--- a/mozilla/layout/tables/nsCellMap.cpp
+++ b/mozilla/layout/tables/nsCellMap.cpp
@@ -478,7 +478,9 @@ nsTableCellMap::InsertRows(nsTableRowGroupFrame& aParent,
       cellMap->InsertRows(*this, aRows, rowIndex, aConsiderSpans, aDamageArea);
       aDamageArea.y = aFirstRowIndex;
       aDamageArea.height = PR_MAX(0, GetRowCount() - aFirstRowIndex);
-      //Dump("after InsertRows");
+#ifdef DEBUG_TABLE_CELLMAP 
+      Dump("after InsertRows");
+#endif
       if (mBCInfo) {
         BCData* bcData;
         PRInt32 count = mBCInfo->mRightBorders.Count();
@@ -536,7 +538,9 @@ nsTableCellMap::RemoveRows(PRInt32         aFirstRowIndex,
     rowIndex -= cellMap->GetRowCount();
     cellMap = cellMap->GetNextSibling();
   }
-  //Dump("after RemoveRows");
+#ifdef DEBUG_TABLE_CELLMAP
+  Dump("after RemoveRows");
+#endif
 }
 
 PRInt32
@@ -582,7 +586,9 @@ nsTableCellMap::AppendCell(nsTableCellFrame& aCellFrame,
     rowIndex -= cellMap->GetRowCount();
     cellMap = cellMap->GetNextSibling();
   }
-  //Dump("after AppendCell");
+#ifdef DEBUG_TABLE_CELLMAP
+  Dump("after AppendCell");
+#endif
   return result;
 }
 
@@ -606,7 +612,9 @@ nsTableCellMap::InsertCells(nsVoidArray&          aCellFrames,
     rowIndex -= cellMap->GetRowCount();
     cellMap = cellMap->GetNextSibling();
   }
-  //Dump("after InsertCells");
+#ifdef DEBUG_TABLE_CELLMAP
+  Dump("after InsertCells");
+#endif
 }
 
 
@@ -628,7 +636,9 @@ nsTableCellMap::RemoveCell(nsTableCellFrame* aCellFrame,
       PRInt32 colIndex;
       aCellFrame->GetColIndex(colIndex);
       aDamageArea.width = PR_MAX(0, GetColCount() - colIndex - 1);
-      //Dump("after RemoveCell");
+#ifdef DEBUG_TABLE_CELLMAP
+      Dump("after RemoveCell");
+#endif
       return;
     }
     rowIndex -= cellMap->GetRowCount();
@@ -1255,7 +1265,15 @@ nsCellMap::AppendCell(nsTableCellMap&   aMap,
 
   // Setup CellData for this cell
   if (origData) {
+    NS_ASSERTION(origData->IsDead(), "replacing a non dead cell is a memory leak");
     origData->Init(aCellFrame);
+    // we are replacing a dead cell, increase the number of cells 
+    // originating at this column
+    nsColInfo* colInfo = aMap.GetColInfoAt(startColIndex);
+    NS_ASSERTION(colInfo, "access to a non existing column");
+    if (colInfo) { 
+      colInfo->mNumCellsOrig++;
+    }
   }
   else {
     origData = (aMap.mBCInfo) ? new BCCellData(aCellFrame) : new CellData(aCellFrame); if (!origData) ABORT1(origData);
@@ -1331,8 +1349,10 @@ nsCellMap::AppendCell(nsTableCellMap&   aMap,
       }
     }
   }
-  //printf("appended cell=%p row=%d \n", aCellFrame, aRowIndex);
-  //aMap.Dump();
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("appended cell=%p row=%d \n", aCellFrame, aRowIndex);
+  aMap.Dump();
+#endif
   return origData;
 }
 
diff --git a/mozilla/layout/tables/nsCellMap.h b/mozilla/layout/tables/nsCellMap.h
index e337d74cbd0..e7696f89677 100644
--- a/mozilla/layout/tables/nsCellMap.h
+++ b/mozilla/layout/tables/nsCellMap.h
@@ -42,6 +42,8 @@
 #include "nsVoidArray.h"
 #include "nsRect.h"
 
+#undef DEBUG_TABLE_CELLMAP
+
 class nsTableColFrame;
 class nsTableCellFrame;
 class nsTableRowGroupFrame;
diff --git a/mozilla/layout/tables/nsTableFrame.cpp b/mozilla/layout/tables/nsTableFrame.cpp
index a656fbfda6c..6b9889f51c5 100644
--- a/mozilla/layout/tables/nsTableFrame.cpp
+++ b/mozilla/layout/tables/nsTableFrame.cpp
@@ -1121,8 +1121,10 @@ nsTableFrame::InsertRows(nsIPresContext&       aPresContext,
                          PRInt32               aRowIndex,
                          PRBool                aConsiderSpans)
 {
-  //printf("insertRowsBefore firstRow=%d \n", aRowIndex);
-  //Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("insertRowsBefore firstRow=%d \n", aRowIndex);
+  Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#endif
 
   PRInt32 numColsToAdd = 0;
   nsTableCellMap* cellMap = GetCellMap();
@@ -1152,9 +1154,10 @@ nsTableFrame::InsertRows(nsIPresContext&       aPresContext,
       SetBCDamageArea(aPresContext, damageArea);
     }
   }
-
-  //printf("insertRowsAfter \n");
-  //Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("insertRowsAfter \n");
+  Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#endif
 
   return numColsToAdd;
 }
@@ -1165,10 +1168,6 @@ void nsTableFrame::RemoveRows(nsIPresContext&  aPresContext,
                               PRInt32          aNumRowsToRemove,
                               PRBool           aConsiderSpans)
 {
-  //printf("removeRowsBefore firstRow=%d numRows=%d\n", aFirstRowIndex, aNumRowsToRemove);
-  //Dump(PR_TRUE, PR_FALSE, PR_TRUE);
-
-  
 #ifdef TBD_OPTIMIZATION
   // decide if we need to rebalance. we have to do this here because the row group 
   // cannot do it when it gets the dirty reflow corresponding to the frame being destroyed
@@ -1186,6 +1185,10 @@ void nsTableFrame::RemoveRows(nsIPresContext&  aPresContext,
 #endif
 
   PRInt32 firstRowIndex = aFirstRowFrame.GetRowIndex();
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("removeRowsBefore firstRow=%d numRows=%d\n", firstRowIndex, aNumRowsToRemove);
+  Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#endif
   nsTableCellMap* cellMap = GetCellMap();
   if (cellMap) {
     nsRect damageArea(0,0,0,0);
@@ -1207,8 +1210,10 @@ void nsTableFrame::RemoveRows(nsIPresContext&  aPresContext,
     }
   }
   AdjustRowIndices(firstRowIndex, -aNumRowsToRemove);
-  //printf("removeRowsAfter\n");
-  //Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#ifdef DEBUG_TABLE_CELLMAP
+  printf("removeRowsAfter\n");
+  Dump(PR_TRUE, PR_FALSE, PR_TRUE);
+#endif
 }
 
 void nsTableFrame::AppendRowGroups(nsIPresContext& aPresContext,
@@ -6056,7 +6061,9 @@ nsTableFrame::CalcBCBorders(nsIPresContext& aPresContext)
   // reset the bc flag and damage area
   SetNeedToCalcBCBorders(PR_FALSE);
   propData->mDamageArea.x = propData->mDamageArea.y = propData->mDamageArea.width = propData->mDamageArea.height = 0;
-  //mCellMap->Dump();
+#ifdef DEBUG_TABLE_CELLMAP
+  mCellMap->Dump();
+#endif
 }
 
 // Iterates over borders (left border, corner, top border) in the cell map within a damage area