diff --git a/mozilla/layout/html/table/src/nsTableRowFrame.cpp b/mozilla/layout/html/table/src/nsTableRowFrame.cpp
index caaa317ead8..256e79ae6ba 100644
--- a/mozilla/layout/html/table/src/nsTableRowFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableRowFrame.cpp
@@ -35,6 +35,7 @@
  *
  * ***** END LICENSE BLOCK ***** */
 #include "nsTableRowFrame.h"
+#include "nsTableRowGroupFrame.h"
 #include "nsIRenderingContext.h"
 #include "nsIPresShell.h"
 #include "nsIPresContext.h"
@@ -114,11 +115,12 @@ nsTableRowFrame::SetFixedHeight(nscoord aValue)
 }
 
 void 
-nsTableRowFrame::SetPctHeight(float aPctValue)
+nsTableRowFrame::SetPctHeight(float  aPctValue,
+                              PRBool aForce)
 {
   nscoord height = PR_MAX(0, NSToCoordRound(aPctValue * 100.0f));
   if (HasPctHeight()) {
-    if (height > mStyleHeight) {
+    if ((height > mStyleHeight) || aForce) {
       mStyleHeight = height;
     }
   }
@@ -520,6 +522,15 @@ nsTableRowFrame::CalcHeight(const nsHTMLReflowState& aReflowState)
                             ? 0 : aReflowState.mComputedHeight;
   ResetHeight(computedHeight);
 
+  const nsStylePosition* position;
+  GetStyleData(eStyleStruct_Position, (const nsStyleStruct*&)position);
+  if (eStyleUnit_Coord == position->mHeight.GetUnit()) {
+    SetFixedHeight(position->mHeight.GetCoordValue());
+  }
+  else if (eStyleUnit_Percent == position->mHeight.GetUnit()) {
+    SetPctHeight(position->mHeight.GetPercentValue());
+  }
+
   for (nsIFrame* kidFrame = mFrames.FirstChild(); kidFrame; kidFrame->GetNextSibling(&kidFrame)) {
     nsCOMPtr<nsIAtom> frameType;
     kidFrame->GetFrameType(getter_AddRefs(frameType));
@@ -1336,12 +1347,22 @@ nsTableRowFrame::Reflow(nsIPresContext*          aPresContext,
   if (!tableFrame) return NS_ERROR_NULL_POINTER;
 
   if ((NS_UNCONSTRAINEDSIZE != aReflowState.availableWidth) &&  !mPrevInFlow) {
-      // see if an extra reflow will be necessary when there is a pct height but no height on the parent 
+      // see if an extra reflow will be necessary when there is a pct height but no height basis 
     if ( ((NS_UNCONSTRAINEDSIZE == aReflowState.mComputedHeight)  || 
-          (0                        == aReflowState.mComputedHeight)) && 
+          (0                    == aReflowState.mComputedHeight)) && 
          nsTableFrame::IsPctHeight(mStyleContext)) {
-      nsTableFrame::NotifyAncestorsOfSpecialReflow(aReflowState);
-      SetNeedSpecialReflow(PR_TRUE);
+      const nsHTMLReflowState* parentRS = aReflowState.parentReflowState;
+      if (parentRS && parentRS->frame) {
+        nsCOMPtr<nsIAtom> fType;
+        parentRS->frame->GetFrameType(getter_AddRefs(fType));
+        if (nsLayoutAtoms::tableRowGroupFrame == fType.get()) {
+          nscoord pctBasis = ((nsTableRowGroupFrame*)parentRS->frame)->GetHeightBasis(*parentRS);
+          if (0 == pctBasis) {
+            nsTableFrame::NotifyAncestorsOfSpecialReflow(aReflowState);
+            SetNeedSpecialReflow(PR_TRUE);
+          }
+        }
+      }
     }
   }
 
diff --git a/mozilla/layout/html/table/src/nsTableRowFrame.h b/mozilla/layout/html/table/src/nsTableRowFrame.h
index a697d4e0902..c6121a5375d 100644
--- a/mozilla/layout/html/table/src/nsTableRowFrame.h
+++ b/mozilla/layout/html/table/src/nsTableRowFrame.h
@@ -236,7 +236,8 @@ public:
   void    SetFixedHeight(nscoord aValue);
 
   float   GetPctHeight() const;
-  void    SetPctHeight(float aPctValue);
+  void    SetPctHeight(float  aPctValue,
+                       PRBool aForce = PR_FALSE);
 
   nscoord GetHeight(nscoord aBasis = 0) const;
 
diff --git a/mozilla/layout/html/table/src/nsTableRowGroupFrame.cpp b/mozilla/layout/html/table/src/nsTableRowGroupFrame.cpp
index fca38c08835..01f14810418 100644
--- a/mozilla/layout/html/table/src/nsTableRowGroupFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableRowGroupFrame.cpp
@@ -560,6 +560,20 @@ nsTableRowGroupFrame::CalculateRowHeights(nsIPresContext*          aPresContext,
   float p2t;
   aPresContext->GetPixelsToTwips(&p2t);
 
+  // make sure that pct height rows do not exceed 100%
+  nscoord pctTotal = 0;
+  nsTableRowFrame* rowFrame;
+  for (rowFrame = GetFirstRow(); rowFrame; rowFrame = rowFrame->GetNextRow()) {
+    if (rowFrame->HasPctHeight()) {
+      nscoord pctHeight = NSToCoordRound(rowFrame->GetPctHeight() * 100.0f);
+      if ((pctHeight + pctTotal) > 100) {
+        pctHeight = PR_MAX(0, NSToCoordRound(100.0f - (float)pctTotal));
+        rowFrame->SetPctHeight((float)pctHeight / 100.0f, PR_TRUE);
+      }
+      pctTotal += pctHeight;
+    }
+  }
+    
   // find the nearest row at or before aStartRowFrameIn that isn't spanned into. 
   // If we have a computed height, then we can't compute the heights
   // incrementally from aStartRowFrameIn, and we must start at the first row.
@@ -605,7 +619,6 @@ nsTableRowGroupFrame::CalculateRowHeights(nsIPresContext*          aPresContext,
   // the largest desired height of each cell, the largest style height of each cell, 
   // the style height of the row.
   nscoord pctHeightBasis = GetHeightBasis(aReflowState);
-  nsTableRowFrame* rowFrame;
   PRInt32 rowIndex; // the index in rowInfo, not among the rows in the row group
   for (rowFrame = startRowFrame, rowIndex = 0; rowFrame; rowFrame = rowFrame->GetNextRow(), rowIndex++) {
     UpdateHeights(rowInfo[rowIndex], nsTableFrame::RoundToPixel(rowFrame->GetHeight(pctHeightBasis), p2t), 
@@ -1326,14 +1339,26 @@ nscoord
 nsTableRowGroupFrame::GetHeightBasis(const nsHTMLReflowState& aReflowState)
 {
   nscoord result = 0;
-  if ((aReflowState.mComputedHeight > 0) && (aReflowState.mComputedHeight < NS_UNCONSTRAINEDSIZE)) {
-    nsTableFrame* tableFrame = nsnull;
-    nsTableFrame::GetTableFrame((nsIFrame*)this, tableFrame);
-    if (tableFrame) {
+  nsTableFrame* tableFrame = nsnull;
+  nsTableFrame::GetTableFrame((nsIFrame*)this, tableFrame);
+  if (tableFrame) {
+    if ((aReflowState.mComputedHeight > 0) && (aReflowState.mComputedHeight < NS_UNCONSTRAINEDSIZE)) {
       nscoord cellSpacing = PR_MAX(0, GetRowCount() - 1) * tableFrame->GetCellSpacingY();
-      result -= cellSpacing;
+      result = aReflowState.mComputedHeight - cellSpacing;
+    }
+    else {
+      const nsHTMLReflowState* parentRS = aReflowState.parentReflowState;
+      if (parentRS && (tableFrame != parentRS->frame)) {
+        parentRS = parentRS->parentReflowState;
+      }
+      if (parentRS && (tableFrame == parentRS->frame) && 
+          (parentRS->mComputedHeight > 0) && (parentRS->mComputedHeight < NS_UNCONSTRAINEDSIZE)) {
+        nscoord cellSpacing = PR_MAX(0, tableFrame->GetRowCount() - 1) * tableFrame->GetCellSpacingY();
+        result = parentRS->mComputedHeight - cellSpacing;
+      }
     }
   }
+
   return result;
 }
 
diff --git a/mozilla/layout/tables/nsTableRowFrame.cpp b/mozilla/layout/tables/nsTableRowFrame.cpp
index caaa317ead8..256e79ae6ba 100644
--- a/mozilla/layout/tables/nsTableRowFrame.cpp
+++ b/mozilla/layout/tables/nsTableRowFrame.cpp
@@ -35,6 +35,7 @@
  *
  * ***** END LICENSE BLOCK ***** */
 #include "nsTableRowFrame.h"
+#include "nsTableRowGroupFrame.h"
 #include "nsIRenderingContext.h"
 #include "nsIPresShell.h"
 #include "nsIPresContext.h"
@@ -114,11 +115,12 @@ nsTableRowFrame::SetFixedHeight(nscoord aValue)
 }
 
 void 
-nsTableRowFrame::SetPctHeight(float aPctValue)
+nsTableRowFrame::SetPctHeight(float  aPctValue,
+                              PRBool aForce)
 {
   nscoord height = PR_MAX(0, NSToCoordRound(aPctValue * 100.0f));
   if (HasPctHeight()) {
-    if (height > mStyleHeight) {
+    if ((height > mStyleHeight) || aForce) {
       mStyleHeight = height;
     }
   }
@@ -520,6 +522,15 @@ nsTableRowFrame::CalcHeight(const nsHTMLReflowState& aReflowState)
                             ? 0 : aReflowState.mComputedHeight;
   ResetHeight(computedHeight);
 
+  const nsStylePosition* position;
+  GetStyleData(eStyleStruct_Position, (const nsStyleStruct*&)position);
+  if (eStyleUnit_Coord == position->mHeight.GetUnit()) {
+    SetFixedHeight(position->mHeight.GetCoordValue());
+  }
+  else if (eStyleUnit_Percent == position->mHeight.GetUnit()) {
+    SetPctHeight(position->mHeight.GetPercentValue());
+  }
+
   for (nsIFrame* kidFrame = mFrames.FirstChild(); kidFrame; kidFrame->GetNextSibling(&kidFrame)) {
     nsCOMPtr<nsIAtom> frameType;
     kidFrame->GetFrameType(getter_AddRefs(frameType));
@@ -1336,12 +1347,22 @@ nsTableRowFrame::Reflow(nsIPresContext*          aPresContext,
   if (!tableFrame) return NS_ERROR_NULL_POINTER;
 
   if ((NS_UNCONSTRAINEDSIZE != aReflowState.availableWidth) &&  !mPrevInFlow) {
-      // see if an extra reflow will be necessary when there is a pct height but no height on the parent 
+      // see if an extra reflow will be necessary when there is a pct height but no height basis 
     if ( ((NS_UNCONSTRAINEDSIZE == aReflowState.mComputedHeight)  || 
-          (0                        == aReflowState.mComputedHeight)) && 
+          (0                    == aReflowState.mComputedHeight)) && 
          nsTableFrame::IsPctHeight(mStyleContext)) {
-      nsTableFrame::NotifyAncestorsOfSpecialReflow(aReflowState);
-      SetNeedSpecialReflow(PR_TRUE);
+      const nsHTMLReflowState* parentRS = aReflowState.parentReflowState;
+      if (parentRS && parentRS->frame) {
+        nsCOMPtr<nsIAtom> fType;
+        parentRS->frame->GetFrameType(getter_AddRefs(fType));
+        if (nsLayoutAtoms::tableRowGroupFrame == fType.get()) {
+          nscoord pctBasis = ((nsTableRowGroupFrame*)parentRS->frame)->GetHeightBasis(*parentRS);
+          if (0 == pctBasis) {
+            nsTableFrame::NotifyAncestorsOfSpecialReflow(aReflowState);
+            SetNeedSpecialReflow(PR_TRUE);
+          }
+        }
+      }
     }
   }
 
diff --git a/mozilla/layout/tables/nsTableRowFrame.h b/mozilla/layout/tables/nsTableRowFrame.h
index a697d4e0902..c6121a5375d 100644
--- a/mozilla/layout/tables/nsTableRowFrame.h
+++ b/mozilla/layout/tables/nsTableRowFrame.h
@@ -236,7 +236,8 @@ public:
   void    SetFixedHeight(nscoord aValue);
 
   float   GetPctHeight() const;
-  void    SetPctHeight(float aPctValue);
+  void    SetPctHeight(float  aPctValue,
+                       PRBool aForce = PR_FALSE);
 
   nscoord GetHeight(nscoord aBasis = 0) const;
 
diff --git a/mozilla/layout/tables/nsTableRowGroupFrame.cpp b/mozilla/layout/tables/nsTableRowGroupFrame.cpp
index fca38c08835..01f14810418 100644
--- a/mozilla/layout/tables/nsTableRowGroupFrame.cpp
+++ b/mozilla/layout/tables/nsTableRowGroupFrame.cpp
@@ -560,6 +560,20 @@ nsTableRowGroupFrame::CalculateRowHeights(nsIPresContext*          aPresContext,
   float p2t;
   aPresContext->GetPixelsToTwips(&p2t);
 
+  // make sure that pct height rows do not exceed 100%
+  nscoord pctTotal = 0;
+  nsTableRowFrame* rowFrame;
+  for (rowFrame = GetFirstRow(); rowFrame; rowFrame = rowFrame->GetNextRow()) {
+    if (rowFrame->HasPctHeight()) {
+      nscoord pctHeight = NSToCoordRound(rowFrame->GetPctHeight() * 100.0f);
+      if ((pctHeight + pctTotal) > 100) {
+        pctHeight = PR_MAX(0, NSToCoordRound(100.0f - (float)pctTotal));
+        rowFrame->SetPctHeight((float)pctHeight / 100.0f, PR_TRUE);
+      }
+      pctTotal += pctHeight;
+    }
+  }
+    
   // find the nearest row at or before aStartRowFrameIn that isn't spanned into. 
   // If we have a computed height, then we can't compute the heights
   // incrementally from aStartRowFrameIn, and we must start at the first row.
@@ -605,7 +619,6 @@ nsTableRowGroupFrame::CalculateRowHeights(nsIPresContext*          aPresContext,
   // the largest desired height of each cell, the largest style height of each cell, 
   // the style height of the row.
   nscoord pctHeightBasis = GetHeightBasis(aReflowState);
-  nsTableRowFrame* rowFrame;
   PRInt32 rowIndex; // the index in rowInfo, not among the rows in the row group
   for (rowFrame = startRowFrame, rowIndex = 0; rowFrame; rowFrame = rowFrame->GetNextRow(), rowIndex++) {
     UpdateHeights(rowInfo[rowIndex], nsTableFrame::RoundToPixel(rowFrame->GetHeight(pctHeightBasis), p2t), 
@@ -1326,14 +1339,26 @@ nscoord
 nsTableRowGroupFrame::GetHeightBasis(const nsHTMLReflowState& aReflowState)
 {
   nscoord result = 0;
-  if ((aReflowState.mComputedHeight > 0) && (aReflowState.mComputedHeight < NS_UNCONSTRAINEDSIZE)) {
-    nsTableFrame* tableFrame = nsnull;
-    nsTableFrame::GetTableFrame((nsIFrame*)this, tableFrame);
-    if (tableFrame) {
+  nsTableFrame* tableFrame = nsnull;
+  nsTableFrame::GetTableFrame((nsIFrame*)this, tableFrame);
+  if (tableFrame) {
+    if ((aReflowState.mComputedHeight > 0) && (aReflowState.mComputedHeight < NS_UNCONSTRAINEDSIZE)) {
       nscoord cellSpacing = PR_MAX(0, GetRowCount() - 1) * tableFrame->GetCellSpacingY();
-      result -= cellSpacing;
+      result = aReflowState.mComputedHeight - cellSpacing;
+    }
+    else {
+      const nsHTMLReflowState* parentRS = aReflowState.parentReflowState;
+      if (parentRS && (tableFrame != parentRS->frame)) {
+        parentRS = parentRS->parentReflowState;
+      }
+      if (parentRS && (tableFrame == parentRS->frame) && 
+          (parentRS->mComputedHeight > 0) && (parentRS->mComputedHeight < NS_UNCONSTRAINEDSIZE)) {
+        nscoord cellSpacing = PR_MAX(0, tableFrame->GetRowCount() - 1) * tableFrame->GetCellSpacingY();
+        result = parentRS->mComputedHeight - cellSpacing;
+      }
     }
   }
+
   return result;
 }