diff --git a/content/base/src/nsStyleContext.cpp b/content/base/src/nsStyleContext.cpp
index d702d1b7bc35..27ac6e57ddd9 100644
--- a/content/base/src/nsStyleContext.cpp
+++ b/content/base/src/nsStyleContext.cpp
@@ -238,6 +238,8 @@ struct StylePositionImpl: public nsStylePosition {
     mHeightFlags = NS_STYLE_POSITION_VALUE_AUTO;
     mHeight = 0;
     mZIndex = 0;
+    mClipFlags = NS_STYLE_CLIP_AUTO;
+    mClip.SizeTo(0,0,0,0);
   }
 
   ~StylePositionImpl(void)
diff --git a/content/html/style/src/nsCSSStyleRule.cpp b/content/html/style/src/nsCSSStyleRule.cpp
index 1fd22b5b9d44..85c763736ceb 100644
--- a/content/html/style/src/nsCSSStyleRule.cpp
+++ b/content/html/style/src/nsCSSStyleRule.cpp
@@ -1017,6 +1017,32 @@ void CSSStyleRuleImpl::MapStyleInto(nsIStyleContext* aContext, nsIPresContext* a
         } else if (ourPosition->mZIndex.GetUnit() == eCSSUnit_Absolute) {
           position->mZIndex = ourPosition->mZIndex.GetIntValue();
         }
+
+        // clip property
+        if (nsnull != ourPosition->mClip) {
+          position->mClipFlags = NS_STYLE_CLIP_RECT;
+
+          if (ourPosition->mClip->mTop.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.top = ourPosition->mClip->mTop.GetIntValue();
+          } else if (ourPosition->mClip->mTop.IsLengthUnit()) {
+            position->mClip.top = CalcLength(ourPosition->mClip->mTop, font, aPresContext);
+          }
+          if (ourPosition->mClip->mRight.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.right = ourPosition->mClip->mRight.GetIntValue();
+          } else if (ourPosition->mClip->mRight.IsLengthUnit()) {
+            position->mClip.right = CalcLength(ourPosition->mClip->mRight, font, aPresContext);
+          }
+          if (ourPosition->mClip->mBottom.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.bottom = ourPosition->mClip->mBottom.GetIntValue();
+          } else if (ourPosition->mClip->mBottom.IsLengthUnit()) {
+            position->mClip.bottom = CalcLength(ourPosition->mClip->mBottom, font, aPresContext);
+          }
+          if (ourPosition->mClip->mLeft.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.left = ourPosition->mClip->mLeft.GetIntValue();
+          } else if (ourPosition->mClip->mLeft.IsLengthUnit()) {
+            position->mClip.left = CalcLength(ourPosition->mClip->mLeft, font, aPresContext);
+          }
+        }
       }
     }
 
diff --git a/layout/base/public/nsIStyleContext.h b/layout/base/public/nsIStyleContext.h
index 672ae5fc702b..9ca1f95832a9 100644
--- a/layout/base/public/nsIStyleContext.h
+++ b/layout/base/public/nsIStyleContext.h
@@ -140,20 +140,22 @@ protected:
 };
 
 struct nsStylePosition : public nsStyleStruct {
-  PRUint8 mPosition;                    // see nsStyleConsts.h
-  PRUint8 mOverflow;                    // see nsStyleConsts.h
+  PRUint8   mPosition;                  // see nsStyleConsts.h
+  PRUint8   mOverflow;                  // see nsStyleConsts.h
+  PRUint8   mClipFlags;                 // see nsStyleConsts.h
 
-  PRUint8 mLeftOffsetFlags;             // see nsStyleConsts.h
-  PRUint8 mTopOffsetFlags;              // see nsStyleConsts.h
-  PRUint8 mWidthFlags;                  // see nsStyleConsts.h
-  PRUint8 mHeightFlags;                 // see nsStyleConsts.h
+  PRUint8   mLeftOffsetFlags;           // see nsStyleConsts.h
+  PRUint8   mTopOffsetFlags;            // see nsStyleConsts.h
+  PRUint8   mWidthFlags;                // see nsStyleConsts.h
+  PRUint8   mHeightFlags;               // see nsStyleConsts.h
 
-  nscoord mLeftOffset;
-  nscoord mTopOffset;
-  nscoord mWidth;
-  nscoord mHeight;
+  nscoord   mLeftOffset;
+  nscoord   mTopOffset;
+  nscoord   mWidth;
+  nscoord   mHeight;
 
-  PRInt32 mZIndex;
+  PRInt32   mZIndex;
+  nsMargin  mClip;                      // offsets from respective edge
 
 protected:
   nsStylePosition();
diff --git a/layout/base/src/nsStyleConsts.h b/layout/base/src/nsStyleConsts.h
index 35421fb1603d..777302eef5de 100644
--- a/layout/base/src/nsStyleConsts.h
+++ b/layout/base/src/nsStyleConsts.h
@@ -70,9 +70,6 @@
 #define NS_STYLE_CLEAR_COLUMN                   6
 #define NS_STYLE_CLEAR_PAGE                     7
 
-// See nsStyleXXX
-#define NS_STYLE_CLIP_AUTO                      0
-
 // See nsStyleColor
 #define NS_STYLE_CURSOR_INHERIT                 0
 #define NS_STYLE_CURSOR_DEFAULT                 1
diff --git a/layout/base/src/nsStyleContext.cpp b/layout/base/src/nsStyleContext.cpp
index d702d1b7bc35..27ac6e57ddd9 100644
--- a/layout/base/src/nsStyleContext.cpp
+++ b/layout/base/src/nsStyleContext.cpp
@@ -238,6 +238,8 @@ struct StylePositionImpl: public nsStylePosition {
     mHeightFlags = NS_STYLE_POSITION_VALUE_AUTO;
     mHeight = 0;
     mZIndex = 0;
+    mClipFlags = NS_STYLE_CLIP_AUTO;
+    mClip.SizeTo(0,0,0,0);
   }
 
   ~StylePositionImpl(void)
diff --git a/layout/html/base/src/nsAbsoluteFrame.cpp b/layout/html/base/src/nsAbsoluteFrame.cpp
index 04d612f0ab57..0036c8043a30 100644
--- a/layout/html/base/src/nsAbsoluteFrame.cpp
+++ b/layout/html/base/src/nsAbsoluteFrame.cpp
@@ -63,9 +63,9 @@ AbsoluteFrame::~AbsoluteFrame()
 {
 }
 
-nsIView* AbsoluteFrame::CreateView(nsIView*      aContainingView,
-                                   const nsRect& aRect,
-                                   PRInt32       aZIndex)
+nsIView* AbsoluteFrame::CreateView(nsIView*         aContainingView,
+                                   const nsRect&    aRect,
+                                   nsStylePosition* aPosition)
 {
   nsIView*  view;
 
@@ -85,17 +85,29 @@ nsIView* AbsoluteFrame::CreateView(nsIView*      aContainingView,
     // See if the containing view is a scroll view
     nsIScrollableView*  scrollView = nsnull;
     nsresult            result;
+    nsRect              clip;
+    nsRect*             pClip = NS_STYLE_CLIP_RECT == aPosition->mClipFlags ?
+                                &clip : nsnull;
+
+    // Is there a clip rect specified?
+    if (NS_STYLE_CLIP_RECT == aPosition->mClipFlags) {
+      // XXX Michael: this needs to change
+      clip.SetRect(aPosition->mClip.left, aPosition->mClip.top,
+                   aPosition->mClip.right, aPosition->mClip.bottom);
+    }
      
     result = aContainingView->QueryInterface(kIScrollableViewIID, (void**)&scrollView);
     if (NS_OK == result) {
       nsIView* scrolledView = scrollView->GetScrolledView();
 
-      view->Init(viewManager, aRect, scrolledView, nsnull, nsnull, nsnull, aZIndex);
+      view->Init(viewManager, aRect, scrolledView, nsnull, nsnull, nsnull,
+        aPosition->mZIndex, pClip);
       viewManager->InsertChild(scrolledView, view, 0);
       NS_RELEASE(scrolledView);
       NS_RELEASE(scrollView);
     } else {
-      view->Init(viewManager, aRect, aContainingView, nsnull, nsnull, nsnull, aZIndex);
+      view->Init(viewManager, aRect, aContainingView, nsnull, nsnull, nsnull,
+        aPosition->mZIndex, pClip);
       viewManager->InsertChild(aContainingView, view, 0);
     }
   
@@ -250,7 +262,7 @@ NS_METHOD AbsoluteFrame::ResizeReflow(nsIPresContext*  aPresContext,
     ComputeViewBounds(containingRect, position, rect);
 
     // Create a view for the frame
-    nsIView*  view = CreateView(containingView, rect, position->mZIndex);
+    nsIView*  view = CreateView(containingView, rect, position);
     NS_RELEASE(containingView);
 
     mFrame->SetView(view);  
diff --git a/layout/html/base/src/nsAbsoluteFrame.h b/layout/html/base/src/nsAbsoluteFrame.h
index e84269153ebc..7046de8b6b34 100644
--- a/layout/html/base/src/nsAbsoluteFrame.h
+++ b/layout/html/base/src/nsAbsoluteFrame.h
@@ -53,9 +53,9 @@ protected:
 
   virtual ~AbsoluteFrame();
 
-  nsIView*  CreateView(nsIView*      aContainingView,
-                       const nsRect& aRect,
-                       PRInt32       aZIndex);
+  nsIView*  CreateView(nsIView*         aContainingView,
+                       const nsRect&    aRect,
+                       nsStylePosition* aPosition);
   nsIFrame* GetContainingBlock();
   void      ComputeViewBounds(const nsRect&    aContainingInnerRect,
                               nsStylePosition* aPosition,
diff --git a/layout/html/style/src/nsCSSStyleRule.cpp b/layout/html/style/src/nsCSSStyleRule.cpp
index 1fd22b5b9d44..85c763736ceb 100644
--- a/layout/html/style/src/nsCSSStyleRule.cpp
+++ b/layout/html/style/src/nsCSSStyleRule.cpp
@@ -1017,6 +1017,32 @@ void CSSStyleRuleImpl::MapStyleInto(nsIStyleContext* aContext, nsIPresContext* a
         } else if (ourPosition->mZIndex.GetUnit() == eCSSUnit_Absolute) {
           position->mZIndex = ourPosition->mZIndex.GetIntValue();
         }
+
+        // clip property
+        if (nsnull != ourPosition->mClip) {
+          position->mClipFlags = NS_STYLE_CLIP_RECT;
+
+          if (ourPosition->mClip->mTop.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.top = ourPosition->mClip->mTop.GetIntValue();
+          } else if (ourPosition->mClip->mTop.IsLengthUnit()) {
+            position->mClip.top = CalcLength(ourPosition->mClip->mTop, font, aPresContext);
+          }
+          if (ourPosition->mClip->mRight.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.right = ourPosition->mClip->mRight.GetIntValue();
+          } else if (ourPosition->mClip->mRight.IsLengthUnit()) {
+            position->mClip.right = CalcLength(ourPosition->mClip->mRight, font, aPresContext);
+          }
+          if (ourPosition->mClip->mBottom.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.bottom = ourPosition->mClip->mBottom.GetIntValue();
+          } else if (ourPosition->mClip->mBottom.IsLengthUnit()) {
+            position->mClip.bottom = CalcLength(ourPosition->mClip->mBottom, font, aPresContext);
+          }
+          if (ourPosition->mClip->mLeft.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.left = ourPosition->mClip->mLeft.GetIntValue();
+          } else if (ourPosition->mClip->mLeft.IsLengthUnit()) {
+            position->mClip.left = CalcLength(ourPosition->mClip->mLeft, font, aPresContext);
+          }
+        }
       }
     }
 
diff --git a/layout/style/nsCSSStyleRule.cpp b/layout/style/nsCSSStyleRule.cpp
index 1fd22b5b9d44..85c763736ceb 100644
--- a/layout/style/nsCSSStyleRule.cpp
+++ b/layout/style/nsCSSStyleRule.cpp
@@ -1017,6 +1017,32 @@ void CSSStyleRuleImpl::MapStyleInto(nsIStyleContext* aContext, nsIPresContext* a
         } else if (ourPosition->mZIndex.GetUnit() == eCSSUnit_Absolute) {
           position->mZIndex = ourPosition->mZIndex.GetIntValue();
         }
+
+        // clip property
+        if (nsnull != ourPosition->mClip) {
+          position->mClipFlags = NS_STYLE_CLIP_RECT;
+
+          if (ourPosition->mClip->mTop.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.top = ourPosition->mClip->mTop.GetIntValue();
+          } else if (ourPosition->mClip->mTop.IsLengthUnit()) {
+            position->mClip.top = CalcLength(ourPosition->mClip->mTop, font, aPresContext);
+          }
+          if (ourPosition->mClip->mRight.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.right = ourPosition->mClip->mRight.GetIntValue();
+          } else if (ourPosition->mClip->mRight.IsLengthUnit()) {
+            position->mClip.right = CalcLength(ourPosition->mClip->mRight, font, aPresContext);
+          }
+          if (ourPosition->mClip->mBottom.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.bottom = ourPosition->mClip->mBottom.GetIntValue();
+          } else if (ourPosition->mClip->mBottom.IsLengthUnit()) {
+            position->mClip.bottom = CalcLength(ourPosition->mClip->mBottom, font, aPresContext);
+          }
+          if (ourPosition->mClip->mLeft.GetUnit() == eCSSUnit_Enumerated) {
+            position->mClip.left = ourPosition->mClip->mLeft.GetIntValue();
+          } else if (ourPosition->mClip->mLeft.IsLengthUnit()) {
+            position->mClip.left = CalcLength(ourPosition->mClip->mLeft, font, aPresContext);
+          }
+        }
       }
     }
 
diff --git a/layout/style/nsStyleContext.cpp b/layout/style/nsStyleContext.cpp
index d702d1b7bc35..27ac6e57ddd9 100644
--- a/layout/style/nsStyleContext.cpp
+++ b/layout/style/nsStyleContext.cpp
@@ -238,6 +238,8 @@ struct StylePositionImpl: public nsStylePosition {
     mHeightFlags = NS_STYLE_POSITION_VALUE_AUTO;
     mHeight = 0;
     mZIndex = 0;
+    mClipFlags = NS_STYLE_CLIP_AUTO;
+    mClip.SizeTo(0,0,0,0);
   }
 
   ~StylePositionImpl(void)