diff --git a/layout/html/table/src/nsTableOuterFrame.cpp b/layout/html/table/src/nsTableOuterFrame.cpp
index abfe42508a5d..cae0540ddb88 100644
--- a/layout/html/table/src/nsTableOuterFrame.cpp
+++ b/layout/html/table/src/nsTableOuterFrame.cpp
@@ -137,18 +137,10 @@ nsresult nsTableOuterFrame::QueryInterface(const nsIID& aIID, void** aInstancePt
   }
 }
 
+// tables change 0 width into auto, trees override this and do nothing
 NS_IMETHODIMP
-nsTableOuterFrame::Init(nsIPresContext*  aPresContext,
-                   nsIContent*           aContent,
-                   nsIFrame*             aParent,
-                   nsIStyleContext*      aContext,
-                   nsIFrame*             aPrevInFlow)
+nsTableOuterFrame::AdjustZeroWidth()
 {
-  nsresult rv = nsHTMLContainerFrame::Init(aPresContext, aContent, aParent, 
-                                           aContext, aPrevInFlow);
-  if (NS_FAILED(rv) || !mStyleContext) return rv;
-
-#if 0
   // a 0 width table becomes auto
   PRBool makeAuto = PR_FALSE;
   nsStylePosition* position = (nsStylePosition*)mStyleContext->GetMutableStyleData(eStyleStruct_Position);
@@ -166,7 +158,21 @@ nsTableOuterFrame::Init(nsIPresContext*  aPresContext,
   if (makeAuto) {
     position->mWidth = nsStyleCoord(eStyleUnit_Auto);
   }
-#endif
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsTableOuterFrame::Init(nsIPresContext*  aPresContext,
+                   nsIContent*           aContent,
+                   nsIFrame*             aParent,
+                   nsIStyleContext*      aContext,
+                   nsIFrame*             aPrevInFlow)
+{
+  nsresult rv = nsHTMLContainerFrame::Init(aPresContext, aContent, aParent, 
+                                           aContext, aPrevInFlow);
+  if (NS_FAILED(rv) || !mStyleContext) return rv;
+  AdjustZeroWidth();
+
   return rv;
 }
 
diff --git a/layout/html/table/src/nsTableOuterFrame.h b/layout/html/table/src/nsTableOuterFrame.h
index 6a0a54f6caa1..1ad22e1bd088 100644
--- a/layout/html/table/src/nsTableOuterFrame.h
+++ b/layout/html/table/src/nsTableOuterFrame.h
@@ -69,6 +69,8 @@ public:
                   nsIStyleContext* aContext,
                   nsIFrame*        aPrevInFlow);
 
+  NS_IMETHOD AdjustZeroWidth();
+
   /**  @see nsIFrame::SetInitialChildList */    
   NS_IMETHOD  SetInitialChildList(nsIPresContext* aPresContext,
                                   nsIAtom*        aListName,
diff --git a/layout/tables/nsTableOuterFrame.cpp b/layout/tables/nsTableOuterFrame.cpp
index abfe42508a5d..cae0540ddb88 100644
--- a/layout/tables/nsTableOuterFrame.cpp
+++ b/layout/tables/nsTableOuterFrame.cpp
@@ -137,18 +137,10 @@ nsresult nsTableOuterFrame::QueryInterface(const nsIID& aIID, void** aInstancePt
   }
 }
 
+// tables change 0 width into auto, trees override this and do nothing
 NS_IMETHODIMP
-nsTableOuterFrame::Init(nsIPresContext*  aPresContext,
-                   nsIContent*           aContent,
-                   nsIFrame*             aParent,
-                   nsIStyleContext*      aContext,
-                   nsIFrame*             aPrevInFlow)
+nsTableOuterFrame::AdjustZeroWidth()
 {
-  nsresult rv = nsHTMLContainerFrame::Init(aPresContext, aContent, aParent, 
-                                           aContext, aPrevInFlow);
-  if (NS_FAILED(rv) || !mStyleContext) return rv;
-
-#if 0
   // a 0 width table becomes auto
   PRBool makeAuto = PR_FALSE;
   nsStylePosition* position = (nsStylePosition*)mStyleContext->GetMutableStyleData(eStyleStruct_Position);
@@ -166,7 +158,21 @@ nsTableOuterFrame::Init(nsIPresContext*  aPresContext,
   if (makeAuto) {
     position->mWidth = nsStyleCoord(eStyleUnit_Auto);
   }
-#endif
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsTableOuterFrame::Init(nsIPresContext*  aPresContext,
+                   nsIContent*           aContent,
+                   nsIFrame*             aParent,
+                   nsIStyleContext*      aContext,
+                   nsIFrame*             aPrevInFlow)
+{
+  nsresult rv = nsHTMLContainerFrame::Init(aPresContext, aContent, aParent, 
+                                           aContext, aPrevInFlow);
+  if (NS_FAILED(rv) || !mStyleContext) return rv;
+  AdjustZeroWidth();
+
   return rv;
 }
 
diff --git a/layout/tables/nsTableOuterFrame.h b/layout/tables/nsTableOuterFrame.h
index 6a0a54f6caa1..1ad22e1bd088 100644
--- a/layout/tables/nsTableOuterFrame.h
+++ b/layout/tables/nsTableOuterFrame.h
@@ -69,6 +69,8 @@ public:
                   nsIStyleContext* aContext,
                   nsIFrame*        aPrevInFlow);
 
+  NS_IMETHOD AdjustZeroWidth();
+
   /**  @see nsIFrame::SetInitialChildList */    
   NS_IMETHOD  SetInitialChildList(nsIPresContext* aPresContext,
                                   nsIAtom*        aListName,
diff --git a/layout/xul/base/src/nsTreeOuterFrame.cpp b/layout/xul/base/src/nsTreeOuterFrame.cpp
index baf7d9aa7cf2..530d009ae37d 100644
--- a/layout/xul/base/src/nsTreeOuterFrame.cpp
+++ b/layout/xul/base/src/nsTreeOuterFrame.cpp
@@ -80,6 +80,13 @@ nsTreeOuterFrame::Init(nsIPresContext*  aPresContext,
   return rv;
 }
 
+NS_IMETHODIMP
+nsTreeOuterFrame::AdjustZeroWidth()
+{
+  // don't do anything, tables change 0 width into auto
+  return NS_OK;
+}
+
 NS_IMETHODIMP 
 nsTreeOuterFrame::HandleEvent(nsIPresContext* aPresContext, 
                              nsGUIEvent*     aEvent,
diff --git a/layout/xul/base/src/nsTreeOuterFrame.h b/layout/xul/base/src/nsTreeOuterFrame.h
index 3ca93ec88b47..53f242916b0b 100644
--- a/layout/xul/base/src/nsTreeOuterFrame.h
+++ b/layout/xul/base/src/nsTreeOuterFrame.h
@@ -45,6 +45,8 @@ public:
                       nsIStyleContext* aContext,
                       nsIFrame*        aPrevInFlow);
 
+  NS_IMETHOD AdjustZeroWidth();
+
   NS_DECL_ISUPPORTS
 
   NS_IMETHOD GetBoxInfo(nsIPresContext* aPresContext, const nsHTMLReflowState& aReflowState, nsBoxInfo& aSize);