diff --git a/mozilla/layout/html/table/src/nsTableFrame.cpp b/mozilla/layout/html/table/src/nsTableFrame.cpp
index d35872870db..6a76a2de85d 100644
--- a/mozilla/layout/html/table/src/nsTableFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableFrame.cpp
@@ -4236,22 +4236,8 @@ nscoord nsTableFrame::ComputeDesiredHeight(nsIPresContext& aPresContext,
         const nsStyleDisplay *rowGroupDisplay;
         rowGroupFrame->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)rowGroupDisplay));
         if (PR_TRUE==IsRowGroup(rowGroupDisplay->mDisplay))
-        { // the rows in rowGroupFrame need to be expanded by rowHeightDelta[i]
-          // and the rowgroup itself needs to be expanded by SUM(row height deltas)
-          nsIFrame * rowFrame=nsnull;
-          rv = rowGroupFrame->FirstChild(nsnull, &rowFrame);
-          while ((NS_SUCCEEDED(rv)) && (nsnull!=rowFrame))
-          {
-            const nsStyleDisplay *rowDisplay;
-            rowFrame->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)rowDisplay));
-            if (NS_STYLE_DISPLAY_TABLE_ROW == rowDisplay->mDisplay)
-            { // the row needs to be expanded by the proportion this row contributed to the original height
-              nsRect rowRect;
-              rowFrame->GetRect(rowRect);
-              sumOfRowHeights += rowRect.height;
-            }
-            rowFrame->GetNextSibling(&rowFrame);
-          }
+        { 
+          ((nsTableRowGroupFrame*)rowGroupFrame)->GetHeightOfRows(sumOfRowHeights);
         }
         rowGroupFrame->GetNextSibling(&rowGroupFrame);
       }
diff --git a/mozilla/layout/html/table/src/nsTableRowGroupFrame.cpp b/mozilla/layout/html/table/src/nsTableRowGroupFrame.cpp
index 1bf004e4c03..561492ecd9a 100644
--- a/mozilla/layout/html/table/src/nsTableRowGroupFrame.cpp
+++ b/mozilla/layout/html/table/src/nsTableRowGroupFrame.cpp
@@ -1294,6 +1294,31 @@ PRBool nsTableRowGroupFrame::NoRowsFollow()
   return result;
 }
 
+NS_METHOD nsTableRowGroupFrame::GetHeightOfRows(nscoord& aResult)
+{
+  // the rows in rowGroupFrame need to be expanded by rowHeightDelta[i]
+  // and the rowgroup itself needs to be expanded by SUM(row height deltas)
+  nsIFrame * rowFrame=nsnull;
+  nsresult rv = FirstChild(nsnull, &rowFrame);
+  while ((NS_SUCCEEDED(rv)) && (nsnull!=rowFrame))
+  {
+    const nsStyleDisplay *rowDisplay;
+    rowFrame->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)rowDisplay));
+    if (NS_STYLE_DISPLAY_TABLE_ROW == rowDisplay->mDisplay)
+    { 
+      nsRect rowRect;
+      rowFrame->GetRect(rowRect);
+      aResult += rowRect.height;
+    }
+    else if (NS_STYLE_DISPLAY_TABLE_ROW_GROUP == rowDisplay->mDisplay)
+    {
+      ((nsTableRowGroupFrame*)rowFrame)->GetHeightOfRows(aResult);
+    }
+    rowFrame->GetNextSibling(&rowFrame);
+  }
+  return NS_OK;
+}
+
 // since we know we're doing an append here, we can optimize
 NS_METHOD nsTableRowGroupFrame::IR_RowAppended(nsIPresContext&      aPresContext,
                                                nsHTMLReflowMetrics& aDesiredSize,
diff --git a/mozilla/layout/html/table/src/nsTableRowGroupFrame.h b/mozilla/layout/html/table/src/nsTableRowGroupFrame.h
index 31290a8b805..b8c97d50b43 100644
--- a/mozilla/layout/html/table/src/nsTableRowGroupFrame.h
+++ b/mozilla/layout/html/table/src/nsTableRowGroupFrame.h
@@ -123,6 +123,12 @@ public:
    */
   nsresult  InitRepeatedFrame(nsTableRowGroupFrame* aHeaderFooterFrame);
 
+  
+  /**
+   * Get the total height of all the row rects
+   */
+  NS_METHOD GetHeightOfRows(nscoord& aResult);
+  
 protected:
 
   /** implement abstract method on nsHTMLContainerFrame */
diff --git a/mozilla/layout/tables/nsTableFrame.cpp b/mozilla/layout/tables/nsTableFrame.cpp
index d35872870db..6a76a2de85d 100644
--- a/mozilla/layout/tables/nsTableFrame.cpp
+++ b/mozilla/layout/tables/nsTableFrame.cpp
@@ -4236,22 +4236,8 @@ nscoord nsTableFrame::ComputeDesiredHeight(nsIPresContext& aPresContext,
         const nsStyleDisplay *rowGroupDisplay;
         rowGroupFrame->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)rowGroupDisplay));
         if (PR_TRUE==IsRowGroup(rowGroupDisplay->mDisplay))
-        { // the rows in rowGroupFrame need to be expanded by rowHeightDelta[i]
-          // and the rowgroup itself needs to be expanded by SUM(row height deltas)
-          nsIFrame * rowFrame=nsnull;
-          rv = rowGroupFrame->FirstChild(nsnull, &rowFrame);
-          while ((NS_SUCCEEDED(rv)) && (nsnull!=rowFrame))
-          {
-            const nsStyleDisplay *rowDisplay;
-            rowFrame->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)rowDisplay));
-            if (NS_STYLE_DISPLAY_TABLE_ROW == rowDisplay->mDisplay)
-            { // the row needs to be expanded by the proportion this row contributed to the original height
-              nsRect rowRect;
-              rowFrame->GetRect(rowRect);
-              sumOfRowHeights += rowRect.height;
-            }
-            rowFrame->GetNextSibling(&rowFrame);
-          }
+        { 
+          ((nsTableRowGroupFrame*)rowGroupFrame)->GetHeightOfRows(sumOfRowHeights);
         }
         rowGroupFrame->GetNextSibling(&rowGroupFrame);
       }
diff --git a/mozilla/layout/tables/nsTableRowGroupFrame.cpp b/mozilla/layout/tables/nsTableRowGroupFrame.cpp
index 1bf004e4c03..561492ecd9a 100644
--- a/mozilla/layout/tables/nsTableRowGroupFrame.cpp
+++ b/mozilla/layout/tables/nsTableRowGroupFrame.cpp
@@ -1294,6 +1294,31 @@ PRBool nsTableRowGroupFrame::NoRowsFollow()
   return result;
 }
 
+NS_METHOD nsTableRowGroupFrame::GetHeightOfRows(nscoord& aResult)
+{
+  // the rows in rowGroupFrame need to be expanded by rowHeightDelta[i]
+  // and the rowgroup itself needs to be expanded by SUM(row height deltas)
+  nsIFrame * rowFrame=nsnull;
+  nsresult rv = FirstChild(nsnull, &rowFrame);
+  while ((NS_SUCCEEDED(rv)) && (nsnull!=rowFrame))
+  {
+    const nsStyleDisplay *rowDisplay;
+    rowFrame->GetStyleData(eStyleStruct_Display, ((const nsStyleStruct *&)rowDisplay));
+    if (NS_STYLE_DISPLAY_TABLE_ROW == rowDisplay->mDisplay)
+    { 
+      nsRect rowRect;
+      rowFrame->GetRect(rowRect);
+      aResult += rowRect.height;
+    }
+    else if (NS_STYLE_DISPLAY_TABLE_ROW_GROUP == rowDisplay->mDisplay)
+    {
+      ((nsTableRowGroupFrame*)rowFrame)->GetHeightOfRows(aResult);
+    }
+    rowFrame->GetNextSibling(&rowFrame);
+  }
+  return NS_OK;
+}
+
 // since we know we're doing an append here, we can optimize
 NS_METHOD nsTableRowGroupFrame::IR_RowAppended(nsIPresContext&      aPresContext,
                                                nsHTMLReflowMetrics& aDesiredSize,
diff --git a/mozilla/layout/tables/nsTableRowGroupFrame.h b/mozilla/layout/tables/nsTableRowGroupFrame.h
index 31290a8b805..b8c97d50b43 100644
--- a/mozilla/layout/tables/nsTableRowGroupFrame.h
+++ b/mozilla/layout/tables/nsTableRowGroupFrame.h
@@ -123,6 +123,12 @@ public:
    */
   nsresult  InitRepeatedFrame(nsTableRowGroupFrame* aHeaderFooterFrame);
 
+  
+  /**
+   * Get the total height of all the row rects
+   */
+  NS_METHOD GetHeightOfRows(nscoord& aResult);
+  
 protected:
 
   /** implement abstract method on nsHTMLContainerFrame */