diff --git a/mozilla/layout/generic/nsContainerFrame.cpp b/mozilla/layout/generic/nsContainerFrame.cpp
index 46678888277..d7d29b498f8 100644
--- a/mozilla/layout/generic/nsContainerFrame.cpp
+++ b/mozilla/layout/generic/nsContainerFrame.cpp
@@ -185,6 +185,25 @@ NS_METHOD nsContainerFrame::FirstChild(nsIFrame*& aFirstChild) const
   return NS_OK;
 }
 
+/////////////////////////////////////////////////////////////////////////////
+// Style support
+
+NS_IMETHODIMP
+nsContainerFrame::ReResolveStyleContext(nsIPresContext* aPresContext,
+                                        nsIStyleContext* aNewParentContext)
+{
+  nsIStyleContext*  oldContext = mStyleContext;
+  nsresult result = nsFrame::ReResolveStyleContext(aPresContext, aNewParentContext);
+  if (oldContext != mStyleContext) {
+    nsIFrame* child = mFirstChild;
+    while ((NS_SUCCEEDED(result)) && (nsnull != child)) {
+      result = child->ReResolveStyleContext(aPresContext, nsnull);
+      child->GetNextSibling(child);
+    }
+  }
+  return result;
+}
+
 /////////////////////////////////////////////////////////////////////////////
 // Painting
 
diff --git a/mozilla/layout/generic/nsContainerFrame.h b/mozilla/layout/generic/nsContainerFrame.h
index d0179ac0522..9f511f52b30 100644
--- a/mozilla/layout/generic/nsContainerFrame.h
+++ b/mozilla/layout/generic/nsContainerFrame.h
@@ -59,6 +59,11 @@ public:
   // IndexOf() returns -1 if the frame is not in the child list.
   NS_IMETHOD  FirstChild(nsIFrame*& aFirstChild) const;
 
+  // re-resolve style context for self and children as necessary
+  // Subclasses need to override if they add child lists
+  NS_IMETHOD  ReResolveStyleContext(nsIPresContext* aPresContext,
+                                    nsIStyleContext* aNewParentContext);
+
   // Debugging
   NS_IMETHOD  List(FILE* out = stdout, PRInt32 aIndent = 0, nsIListFilter *aFilter = nsnull) const;
   NS_IMETHOD  VerifyTree() const;
diff --git a/mozilla/layout/generic/nsFrame.cpp b/mozilla/layout/generic/nsFrame.cpp
index 07a83267b24..fcc513890e4 100644
--- a/mozilla/layout/generic/nsFrame.cpp
+++ b/mozilla/layout/generic/nsFrame.cpp
@@ -346,15 +346,9 @@ NS_IMETHODIMP nsFrame::GetContent(nsIContent*& aContent) const
   return NS_OK;
 }
 
-NS_IMETHODIMP nsFrame::GetStyleContext(nsIPresContext*   aPresContext,
-                                   nsIStyleContext*& aStyleContext)
+NS_IMETHODIMP nsFrame::GetStyleContext(nsIStyleContext*& aStyleContext) const
 {
-  if ((nsnull == mStyleContext) && (nsnull != aPresContext)) {
-    mStyleContext = aPresContext->ResolveStyleContextFor(mContent, mGeometricParent); // XXX should be content parent???
-    if (nsnull != mStyleContext) {
-      DidSetStyleContext(aPresContext);
-    }
-  }
+  NS_ASSERTION(nsnull != mStyleContext, "frame should always have style context");
   NS_IF_ADDREF(mStyleContext);
   aStyleContext = mStyleContext;
   return NS_OK;
@@ -392,6 +386,45 @@ NS_IMETHODIMP nsFrame::GetStyleData(nsStyleStructID aSID, const nsStyleStruct*&
   return NS_OK;
 }
 
+NS_IMETHODIMP nsFrame::ReResolveStyleContext(nsIPresContext* aPresContext,
+                                             nsIStyleContext* aNewParentContext)
+{
+  NS_ASSERTION(nsnull != mStyleContext, "null style context");
+  if (nsnull != mStyleContext) {
+    nsIAtom*  pseudoTag = nsnull;
+    mStyleContext->GetPseudoType(pseudoTag);
+    nsIStyleContext*  parent = aNewParentContext;
+    if (nsnull == aNewParentContext) {
+      parent = mStyleContext->GetParent();
+    }
+    nsIStyleContext*  newContext;
+    if (nsnull != pseudoTag) {
+      newContext = 
+        aPresContext->ResolvePseudoStyleContextFor(mContent, pseudoTag, parent);
+    }
+    else {
+      newContext = aPresContext->ResolveStyleContextFor(mContent, parent);
+    }
+    if (nsnull == aNewParentContext) {
+      NS_IF_RELEASE(parent);
+    }
+
+    NS_ASSERTION(nsnull != newContext, "failed to get new style context");
+    if (nsnull != newContext) {
+      if (newContext != mStyleContext) {
+        NS_RELEASE(mStyleContext);
+        mStyleContext = newContext;
+        DidSetStyleContext(aPresContext);
+      }
+      else {
+        NS_RELEASE(newContext);
+        mStyleContext->RemapStyle(aPresContext);
+      }
+    }
+  }
+  return NS_OK;
+}
+
 // Geometric and content parent member functions
 
 NS_IMETHODIMP nsFrame::GetContentParent(nsIFrame*& aParent) const
diff --git a/mozilla/layout/generic/nsFrame.h b/mozilla/layout/generic/nsFrame.h
index ed3ab611fa0..319265a31ef 100644
--- a/mozilla/layout/generic/nsFrame.h
+++ b/mozilla/layout/generic/nsFrame.h
@@ -116,12 +116,13 @@ public:
   NS_IMETHOD  DeleteFrame(nsIPresContext& aPresContext);
   NS_IMETHOD  SizeOf(nsISizeOfHandler* aHandler) const;
   NS_IMETHOD  GetContent(nsIContent*& aContent) const;
-  NS_IMETHOD  GetStyleContext(nsIPresContext* aContext,
-                              nsIStyleContext*& aStyleContext);
+  NS_IMETHOD  GetStyleContext(nsIStyleContext*& aStyleContext) const;
   NS_IMETHOD  SetStyleContext(nsIPresContext* aPresContext,
                               nsIStyleContext* aContext);
   NS_IMETHOD  GetStyleData(nsStyleStructID aSID,
                            const nsStyleStruct*& aStyleStruct) const;
+  NS_IMETHOD  ReResolveStyleContext(nsIPresContext* aPresContext,
+                                    nsIStyleContext* aNewParentContext);
   NS_IMETHOD  GetContentParent(nsIFrame*& aParent) const;
   NS_IMETHOD  SetContentParent(const nsIFrame* aParent);
   NS_IMETHOD  GetGeometricParent(nsIFrame*& aParent) const;
diff --git a/mozilla/layout/html/base/src/nsContainerFrame.cpp b/mozilla/layout/html/base/src/nsContainerFrame.cpp
index 46678888277..d7d29b498f8 100644
--- a/mozilla/layout/html/base/src/nsContainerFrame.cpp
+++ b/mozilla/layout/html/base/src/nsContainerFrame.cpp
@@ -185,6 +185,25 @@ NS_METHOD nsContainerFrame::FirstChild(nsIFrame*& aFirstChild) const
   return NS_OK;
 }
 
+/////////////////////////////////////////////////////////////////////////////
+// Style support
+
+NS_IMETHODIMP
+nsContainerFrame::ReResolveStyleContext(nsIPresContext* aPresContext,
+                                        nsIStyleContext* aNewParentContext)
+{
+  nsIStyleContext*  oldContext = mStyleContext;
+  nsresult result = nsFrame::ReResolveStyleContext(aPresContext, aNewParentContext);
+  if (oldContext != mStyleContext) {
+    nsIFrame* child = mFirstChild;
+    while ((NS_SUCCEEDED(result)) && (nsnull != child)) {
+      result = child->ReResolveStyleContext(aPresContext, nsnull);
+      child->GetNextSibling(child);
+    }
+  }
+  return result;
+}
+
 /////////////////////////////////////////////////////////////////////////////
 // Painting
 
diff --git a/mozilla/layout/html/base/src/nsContainerFrame.h b/mozilla/layout/html/base/src/nsContainerFrame.h
index d0179ac0522..9f511f52b30 100644
--- a/mozilla/layout/html/base/src/nsContainerFrame.h
+++ b/mozilla/layout/html/base/src/nsContainerFrame.h
@@ -59,6 +59,11 @@ public:
   // IndexOf() returns -1 if the frame is not in the child list.
   NS_IMETHOD  FirstChild(nsIFrame*& aFirstChild) const;
 
+  // re-resolve style context for self and children as necessary
+  // Subclasses need to override if they add child lists
+  NS_IMETHOD  ReResolveStyleContext(nsIPresContext* aPresContext,
+                                    nsIStyleContext* aNewParentContext);
+
   // Debugging
   NS_IMETHOD  List(FILE* out = stdout, PRInt32 aIndent = 0, nsIListFilter *aFilter = nsnull) const;
   NS_IMETHOD  VerifyTree() const;
diff --git a/mozilla/layout/html/base/src/nsFrame.cpp b/mozilla/layout/html/base/src/nsFrame.cpp
index 07a83267b24..fcc513890e4 100644
--- a/mozilla/layout/html/base/src/nsFrame.cpp
+++ b/mozilla/layout/html/base/src/nsFrame.cpp
@@ -346,15 +346,9 @@ NS_IMETHODIMP nsFrame::GetContent(nsIContent*& aContent) const
   return NS_OK;
 }
 
-NS_IMETHODIMP nsFrame::GetStyleContext(nsIPresContext*   aPresContext,
-                                   nsIStyleContext*& aStyleContext)
+NS_IMETHODIMP nsFrame::GetStyleContext(nsIStyleContext*& aStyleContext) const
 {
-  if ((nsnull == mStyleContext) && (nsnull != aPresContext)) {
-    mStyleContext = aPresContext->ResolveStyleContextFor(mContent, mGeometricParent); // XXX should be content parent???
-    if (nsnull != mStyleContext) {
-      DidSetStyleContext(aPresContext);
-    }
-  }
+  NS_ASSERTION(nsnull != mStyleContext, "frame should always have style context");
   NS_IF_ADDREF(mStyleContext);
   aStyleContext = mStyleContext;
   return NS_OK;
@@ -392,6 +386,45 @@ NS_IMETHODIMP nsFrame::GetStyleData(nsStyleStructID aSID, const nsStyleStruct*&
   return NS_OK;
 }
 
+NS_IMETHODIMP nsFrame::ReResolveStyleContext(nsIPresContext* aPresContext,
+                                             nsIStyleContext* aNewParentContext)
+{
+  NS_ASSERTION(nsnull != mStyleContext, "null style context");
+  if (nsnull != mStyleContext) {
+    nsIAtom*  pseudoTag = nsnull;
+    mStyleContext->GetPseudoType(pseudoTag);
+    nsIStyleContext*  parent = aNewParentContext;
+    if (nsnull == aNewParentContext) {
+      parent = mStyleContext->GetParent();
+    }
+    nsIStyleContext*  newContext;
+    if (nsnull != pseudoTag) {
+      newContext = 
+        aPresContext->ResolvePseudoStyleContextFor(mContent, pseudoTag, parent);
+    }
+    else {
+      newContext = aPresContext->ResolveStyleContextFor(mContent, parent);
+    }
+    if (nsnull == aNewParentContext) {
+      NS_IF_RELEASE(parent);
+    }
+
+    NS_ASSERTION(nsnull != newContext, "failed to get new style context");
+    if (nsnull != newContext) {
+      if (newContext != mStyleContext) {
+        NS_RELEASE(mStyleContext);
+        mStyleContext = newContext;
+        DidSetStyleContext(aPresContext);
+      }
+      else {
+        NS_RELEASE(newContext);
+        mStyleContext->RemapStyle(aPresContext);
+      }
+    }
+  }
+  return NS_OK;
+}
+
 // Geometric and content parent member functions
 
 NS_IMETHODIMP nsFrame::GetContentParent(nsIFrame*& aParent) const
diff --git a/mozilla/layout/html/base/src/nsFrame.h b/mozilla/layout/html/base/src/nsFrame.h
index ed3ab611fa0..319265a31ef 100644
--- a/mozilla/layout/html/base/src/nsFrame.h
+++ b/mozilla/layout/html/base/src/nsFrame.h
@@ -116,12 +116,13 @@ public:
   NS_IMETHOD  DeleteFrame(nsIPresContext& aPresContext);
   NS_IMETHOD  SizeOf(nsISizeOfHandler* aHandler) const;
   NS_IMETHOD  GetContent(nsIContent*& aContent) const;
-  NS_IMETHOD  GetStyleContext(nsIPresContext* aContext,
-                              nsIStyleContext*& aStyleContext);
+  NS_IMETHOD  GetStyleContext(nsIStyleContext*& aStyleContext) const;
   NS_IMETHOD  SetStyleContext(nsIPresContext* aPresContext,
                               nsIStyleContext* aContext);
   NS_IMETHOD  GetStyleData(nsStyleStructID aSID,
                            const nsStyleStruct*& aStyleStruct) const;
+  NS_IMETHOD  ReResolveStyleContext(nsIPresContext* aPresContext,
+                                    nsIStyleContext* aNewParentContext);
   NS_IMETHOD  GetContentParent(nsIFrame*& aParent) const;
   NS_IMETHOD  SetContentParent(const nsIFrame* aParent);
   NS_IMETHOD  GetGeometricParent(nsIFrame*& aParent) const;