diff --git a/content/svg/content/src/nsSVGAnimatedString.cpp b/content/svg/content/src/nsSVGAnimatedString.cpp
index cec616713db1..e0ea3e1f8d16 100644
--- a/content/svg/content/src/nsSVGAnimatedString.cpp
+++ b/content/svg/content/src/nsSVGAnimatedString.cpp
@@ -41,13 +41,49 @@
 #include "nsSVGAnimatedString.h"
 #include "nsContentUtils.h"
 
+
+////////////////////////////////////////////////////////////////////////
+// nsSVGAnimatedString
+
+class nsSVGAnimatedString : public nsIDOMSVGAnimatedString,
+                            public nsSVGValue
+{
+protected:
+  friend nsresult NS_NewSVGAnimatedString(nsIDOMSVGAnimatedString** result);
+  nsSVGAnimatedString();
+  ~nsSVGAnimatedString();
+  void Init();
+  
+public:
+  // nsISupports interface:
+  NS_DECL_ISUPPORTS
+
+  // nsIDOMSVGAnimatedString interface:
+  NS_DECL_NSIDOMSVGANIMATEDSTRING
+
+  // remainder of nsISVGValue interface:
+  NS_IMETHOD SetValueString(const nsAString& aValue);
+  NS_IMETHOD GetValueString(nsAString& aValue);
+
+protected:
+  nsString mBaseVal;
+};
+
+
 //----------------------------------------------------------------------
 // Implementation
 
-void
-nsSVGAnimatedString::Clear()
+nsSVGAnimatedString::nsSVGAnimatedString()
+{
+}
+
+nsSVGAnimatedString::~nsSVGAnimatedString()
+{
+}
+
+void
+nsSVGAnimatedString::Init()
 {
-  mBaseVal.Truncate();
 }
 
 //----------------------------------------------------------------------
@@ -121,6 +157,8 @@ NS_NewSVGAnimatedString(nsIDOMSVGAnimatedString** aResult)
   if(!animatedString) return NS_ERROR_OUT_OF_MEMORY;
   NS_ADDREF(animatedString);
 
+  animatedString->Init();
+  
   *aResult = (nsIDOMSVGAnimatedString*) animatedString;
   
   return NS_OK;
diff --git a/content/svg/content/src/nsSVGAnimatedString.h b/content/svg/content/src/nsSVGAnimatedString.h
index b7bae387810b..60685665b227 100644
--- a/content/svg/content/src/nsSVGAnimatedString.h
+++ b/content/svg/content/src/nsSVGAnimatedString.h
@@ -40,34 +40,10 @@
 #define __NS_SVGANIMATEDSTRING_H__
 
 #include "nsIDOMSVGAnimatedString.h"
-#include "nsSVGValue.h"
 
 nsresult NS_NewSVGAnimatedString(nsIDOMSVGAnimatedString** result);
 
-////////////////////////////////////////////////////////////////////////
-// nsSVGAnimatedString
 
-class nsSVGAnimatedString : public nsIDOMSVGAnimatedString,
-                            public nsSVGValue
-{
-protected:
-  friend nsresult NS_NewSVGAnimatedString(nsIDOMSVGAnimatedString** result);
 
-public:
-  // nsISupports interface:
-  NS_DECL_ISUPPORTS
-
-  // nsIDOMSVGAnimatedString interface:
-  NS_DECL_NSIDOMSVGANIMATEDSTRING
-
-  // remainder of nsISVGValue interface:
-  NS_IMETHOD SetValueString(const nsAString& aValue);
-  NS_IMETHOD GetValueString(nsAString& aValue);
-
-  void Clear();
-
-protected:
-  nsString mBaseVal;
-};
 
 #endif //__NS_SVGANIMATEDSTRING_H__
diff --git a/content/svg/content/src/nsSVGElement.cpp b/content/svg/content/src/nsSVGElement.cpp
index 165963f42b3f..6d861cfd3a37 100644
--- a/content/svg/content/src/nsSVGElement.cpp
+++ b/content/svg/content/src/nsSVGElement.cpp
@@ -69,25 +69,6 @@
 #include "nsSVGNumber2.h"
 #include "nsSVGEnum.h"
 #include "nsIDOMSVGUnitTypes.h"
-#include "nsIDOMSVGAngle.h"
-#include "nsIDOMSVGAnimatedAngle.h"
-#include "nsIDOMSVGAnimatedBoolean.h"
-#include "nsIDOMSVGAnimatedInteger.h"
-#include "nsIDOMSVGLength.h"
-#include "nsIDOMSVGLengthList.h"
-#include "nsIDOMSVGAnimatedLengthList.h"
-#include "nsIDOMSVGNumberList.h"
-#include "nsIDOMSVGAnimatedNumberList.h"
-#include "nsIDOMSVGPointList.h"
-#include "nsIDOMSVGAnimatedPoints.h"
-#include "nsIDOMSVGPresAspectRatio.h"
-#include "nsIDOMSVGAnimPresAspRatio.h"
-#include "nsIDOMSVGTransformList.h"
-#include "nsIDOMSVGAnimTransformList.h"
-#include "nsIDOMSVGAnimatedString.h"
-#include "nsIDOMSVGAnimatedRect.h"
-#include "nsSVGRect.h"
-#include "nsSVGAnimatedString.h"
 #include <stdarg.h>
 
 nsSVGEnumMapping nsSVGElement::sSVGUnitTypesMap[] = {
@@ -336,62 +317,6 @@ nsSVGElement::UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
           break;
         }
       }
-
-      // Now check for one of the old style basetypes going away
-      nsCOMPtr<nsISVGValue> svg_value = GetMappedAttribute(aNamespaceID, aName);
-
-      if (svg_value) {
-#ifdef DEBUG_tor
-        nsCOMPtr<nsIDOMSVGAnimatedAngle> a = do_QueryInterface(svg_value);
-        NS_ASSERTION(!a, "must provide element processing for unset angle");
-
-        nsCOMPtr<nsIDOMSVGAnimatedBoolean> b = do_QueryInterface(svg_value);
-        NS_ASSERTION(!b, "must provide element processing for unset boolean");
-
-        nsCOMPtr<nsIDOMSVGAnimatedInteger> i = do_QueryInterface(svg_value);
-        NS_ASSERTION(!i, "must provide element processing for unset integer");
-#endif
-
-        nsCOMPtr<nsIDOMSVGAnimatedRect> r = do_QueryInterface(svg_value);
-        if (r) {
-          nsIDOMSVGRect *rect;
-          r->GetBaseVal(&rect);
-          static_cast<nsSVGRect*>(rect)->Clear();
-        }
-        nsCOMPtr<nsIDOMSVGAnimatedPreserveAspectRatio> ar = do_QueryInterface(svg_value);
-        if (ar) {
-          nsIDOMSVGPreserveAspectRatio *par;
-          ar->GetBaseVal(&par);
-          par->SetAlign(nsIDOMSVGPreserveAspectRatio::SVG_PRESERVEASPECTRATIO_XMIDYMID);
-          par->SetMeetOrSlice(nsIDOMSVGPreserveAspectRatio::SVG_MEETORSLICE_MEET);
-        }
-        nsCOMPtr<nsIDOMSVGAnimatedString> s = do_QueryInterface(svg_value);
-        if (s) {
-          static_cast<nsSVGAnimatedString*>(s.get())->Clear();
-        }
-        nsCOMPtr<nsIDOMSVGPointList> pl = do_QueryInterface(svg_value);
-        if (pl) {
-          pl->Clear();
-        }
-        nsCOMPtr<nsIDOMSVGAnimatedLengthList> ll = do_QueryInterface(svg_value);
-        if (ll) {
-          nsIDOMSVGLengthList *lengthlist;
-          ll->GetBaseVal(&lengthlist);
-          lengthlist->Clear();
-        }
-        nsCOMPtr<nsIDOMSVGAnimatedNumberList> nl = do_QueryInterface(svg_value);
-        if (nl) {
-          nsIDOMSVGNumberList *numberlist;
-          nl->GetBaseVal(&numberlist);
-          numberlist->Clear();
-        }
-        nsCOMPtr<nsIDOMSVGAnimatedTransformList> tl = do_QueryInterface(svg_value);
-        if (tl) {
-          nsIDOMSVGTransformList *transform;
-          tl->GetBaseVal(&transform);
-          transform->Clear();
-        }
-      }
     }
   }
 
diff --git a/content/svg/content/src/nsSVGFilterElement.cpp b/content/svg/content/src/nsSVGFilterElement.cpp
index 6845bbb98c47..25b49a7fe4ca 100644
--- a/content/svg/content/src/nsSVGFilterElement.cpp
+++ b/content/svg/content/src/nsSVGFilterElement.cpp
@@ -238,20 +238,6 @@ nsSVGFilterElement::SetAttr(PRInt32 aNameSpaceID, nsIAtom* aName,
   return rv;
 }
 
-nsresult
-nsSVGFilterElement::UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
-                              PRBool aNotify)
-{
-  if (aName == nsGkAtoms::filterRes && aNamespaceID == kNameSpaceID_None) {
-    mFilterResX->SetBaseVal(0);
-    mFilterResY->SetBaseVal(0);
-
-    return nsGenericElement::UnsetAttr(aNamespaceID, aName, aNotify);
-  }
-
-  return nsSVGFilterElementBase::UnsetAttr(aNamespaceID, aName, aNotify);
-}
-
 NS_IMETHODIMP_(PRBool)
 nsSVGFilterElement::IsAttributeMapped(const nsIAtom* name) const
 {
diff --git a/content/svg/content/src/nsSVGFilterElement.h b/content/svg/content/src/nsSVGFilterElement.h
index b4d418b14294..bb115ffda6fa 100644
--- a/content/svg/content/src/nsSVGFilterElement.h
+++ b/content/svg/content/src/nsSVGFilterElement.h
@@ -79,8 +79,6 @@ public:
   virtual nsresult SetAttr(PRInt32 aNameSpaceID, nsIAtom* aName,
                            nsIAtom* aPrefix, const nsAString& aValue,
                            PRBool aNotify);
-  virtual nsresult UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
-                             PRBool aNotify);
 
   virtual nsresult Clone(nsINodeInfo *aNodeInfo, nsINode **aResult) const;
   NS_IMETHOD_(PRBool) IsAttributeMapped(const nsIAtom* aAttribute) const;
diff --git a/content/svg/content/src/nsSVGFilters.cpp b/content/svg/content/src/nsSVGFilters.cpp
index 8072de0a8110..0aa2e3964990 100644
--- a/content/svg/content/src/nsSVGFilters.cpp
+++ b/content/svg/content/src/nsSVGFilters.cpp
@@ -3010,8 +3010,6 @@ public:
                                 const nsAString& aValue,
                                 nsAttrValue& aResult);
   virtual nsresult Clone(nsINodeInfo *aNodeInfo, nsINode **aResult) const;
-  virtual nsresult UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
-                             PRBool aNotify);
 
 protected:
   virtual NumberAttributesInfo GetNumberInfo();
@@ -3236,18 +3234,6 @@ nsSVGFETurbulenceElement::ParseAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
                                                       aValue, aResult);
 }
 
-nsresult
-nsSVGFETurbulenceElement::UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
-                                    PRBool aNotify)
-{
-  if (aNamespaceID == kNameSpaceID_None && aName == nsGkAtoms::numOctaves) {
-    mNumOctaves->SetBaseVal(1);
-    return nsGenericElement::UnsetAttr(aNamespaceID, aName, aNotify);
-  }
-
-  return nsSVGFETurbulenceElementBase::UnsetAttr(aNamespaceID, aName, aNotify);
-}
-
 NS_IMETHODIMP
 nsSVGFETurbulenceElement::Filter(nsSVGFilterInstance *instance)
 {
@@ -3849,8 +3835,6 @@ public:
                                 const nsAString& aValue,
                                 nsAttrValue& aResult);
   virtual nsresult Clone(nsINodeInfo *aNodeInfo, nsINode **aResult) const;
-  virtual nsresult UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
-                             PRBool aNotify);
 
 protected:
   virtual PRBool OperatesOnPremultipledAlpha() {
@@ -3967,7 +3951,7 @@ nsSVGFEConvolveMatrixElement::Init()
     NS_ENSURE_SUCCESS(rv,rv);
   }
 
-  // DOM property: preserveAlpha , #IMPLIED attrib: preserveAlpha
+  // DOM property: targetY , #IMPLIED attrib: targetY
   {
     rv = NS_NewSVGAnimatedBoolean(getter_AddRefs(mPreserveAlpha), PR_FALSE);
     NS_ENSURE_SUCCESS(rv,rv);
@@ -4135,35 +4119,6 @@ nsSVGFEConvolveMatrixElement::ParseAttribute(PRInt32 aNameSpaceID, nsIAtom* aNam
                                                           aValue, aResult);
 }
 
-nsresult
-nsSVGFEConvolveMatrixElement::UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
-                                    PRBool aNotify)
-{
-  if (aNamespaceID == kNameSpaceID_None) {
-    PRBool processed = PR_FALSE;
-    if (aName == nsGkAtoms::order) {
-      mOrderX->SetBaseVal(0);
-      mOrderY->SetBaseVal(0);
-      processed = PR_TRUE;
-    } else if (aName == nsGkAtoms::targetX) {
-      mTargetX->SetBaseVal(0);
-      processed = PR_TRUE;
-    } else if (aName == nsGkAtoms::targetY) {
-      mTargetY->SetBaseVal(0);
-      processed = PR_TRUE;
-    } else if (aName == nsGkAtoms::preserveAlpha) {
-      mPreserveAlpha->SetBaseVal(PR_FALSE);
-      processed = PR_TRUE;
-    }
-
-    if (processed) {
-      return nsGenericElement::UnsetAttr(aNamespaceID, aName, aNotify);
-    }
-  }
-
-  return nsSVGFEConvolveMatrixElementBase::UnsetAttr(aNamespaceID, aName, aNotify);
-}
-
 #define BOUND(val, min, max) \
   PR_MIN(PR_MAX(val, min), max)
 
diff --git a/content/svg/content/src/nsSVGMarkerElement.cpp b/content/svg/content/src/nsSVGMarkerElement.cpp
index a509740aed75..eb71fc3a9082 100644
--- a/content/svg/content/src/nsSVGMarkerElement.cpp
+++ b/content/svg/content/src/nsSVGMarkerElement.cpp
@@ -306,13 +306,7 @@ nsSVGMarkerElement::UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
       vb->SetHeight(mLengthAttributes[MARKERHEIGHT].GetAnimValue(mCoordCtx));
     } else if (aName == nsGkAtoms::orient) {
       mOrientType.SetBaseValue(SVG_MARKER_ORIENT_AUTO, this, PR_FALSE);
-      nsIDOMSVGAngle *angle;
-      mOrient->GetBaseVal(&angle);
-      angle->NewValueSpecifiedUnits(nsIDOMSVGAngle::SVG_ANGLETYPE_UNSPECIFIED,
-                                    0.0f);
     }
-
-    return nsGenericElement::UnsetAttr(aNamespaceID, aName, aNotify);
   }
 
   return nsSVGMarkerElementBase::UnsetAttr(aNamespaceID, aName, aNotify);
diff --git a/content/svg/content/src/nsSVGPathElement.cpp b/content/svg/content/src/nsSVGPathElement.cpp
index a79c9317e5f6..648ad6b16eb9 100644
--- a/content/svg/content/src/nsSVGPathElement.cpp
+++ b/content/svg/content/src/nsSVGPathElement.cpp
@@ -442,24 +442,6 @@ nsSVGPathElement::BeforeSetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
                                              aValue, aNotify);
 }
 
-nsresult
-nsSVGPathElement::UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
-                            PRBool aNotify)
-{
-  if (aNamespaceID == kNameSpaceID_None && aName == nsGkAtoms::d) {
-    if (mSegments) {
-      NS_REMOVE_SVGVALUE_OBSERVER(mSegments);
-      mSegments = nsnull;
-    }
-
-    mPathData.Clear();
-
-    return nsGenericElement::UnsetAttr(aNamespaceID, aName, aNotify);
-  }
-
-  return nsSVGPathElementBase::UnsetAttr(aNamespaceID, aName, aNotify);
-}
-
 NS_IMETHODIMP
 nsSVGPathElement::DidModifySVGObservable(nsISVGValue* observable,
                                          nsISVGValue::modificationType aModType)
diff --git a/content/svg/content/src/nsSVGPathElement.h b/content/svg/content/src/nsSVGPathElement.h
index 98ec22b1c29d..0ca812d415e8 100644
--- a/content/svg/content/src/nsSVGPathElement.h
+++ b/content/svg/content/src/nsSVGPathElement.h
@@ -56,9 +56,10 @@ public:
   nsSVGPathList() : mArguments(nsnull), mNumCommands(0), mNumArguments(0) {}
   ~nsSVGPathList() { Clear(); }
   void Playback(gfxContext *aCtx);
-  void Clear();
 
 protected:
+  void Clear();
+
   float   *mArguments;
   PRUint32 mNumCommands;
   PRUint32 mNumArguments;
@@ -105,17 +106,13 @@ public:
 
   virtual already_AddRefed<gfxFlattenedPath> GetFlattenedPath(nsIDOMSVGMatrix *aMatrix);
 
-  // nsIContent interface
   virtual nsresult Clone(nsINodeInfo *aNodeInfo, nsINode **aResult) const;
-  virtual nsresult BeforeSetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
-                                 const nsAString* aValue, PRBool aNotify);
-  virtual nsresult UnsetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
-                             PRBool aNotify);
 
 protected:
 
-  // nsSVGElement method
   virtual NumberAttributesInfo GetNumberInfo();
+  virtual nsresult BeforeSetAttr(PRInt32 aNamespaceID, nsIAtom* aName,
+                                 const nsAString* aValue, PRBool aNotify);
 
   // Helper for lazily creating pathseg list
   nsresult CreatePathSegList();
diff --git a/content/svg/content/src/nsSVGRect.cpp b/content/svg/content/src/nsSVGRect.cpp
index caf8cd0822d3..074238b59814 100644
--- a/content/svg/content/src/nsSVGRect.cpp
+++ b/content/svg/content/src/nsSVGRect.cpp
@@ -48,6 +48,30 @@
 #include "nsContentUtils.h"
 #include "nsDOMError.h"
 
+////////////////////////////////////////////////////////////////////////
+// nsSVGRect class
+
+class nsSVGRect : public nsIDOMSVGRect,
+                  public nsSVGValue
+{
+public:
+  nsSVGRect(float x=0.0f, float y=0.0f, float w=0.0f, float h=0.0f);
+  
+  // nsISupports interface:
+  NS_DECL_ISUPPORTS
+
+  // nsIDOMSVGRect interface:
+  NS_DECL_NSIDOMSVGRECT
+
+  // nsISVGValue interface:
+  NS_IMETHOD SetValueString(const nsAString& aValue);
+  NS_IMETHOD GetValueString(nsAString& aValue);
+
+
+protected:
+  float mX, mY, mWidth, mHeight;
+};
+
 //----------------------------------------------------------------------
 // implementation:
 
@@ -56,12 +80,6 @@ nsSVGRect::nsSVGRect(float x, float y, float w, float h)
 {
 }
 
-void
-nsSVGRect::Clear()
-{
-  mX = mY = mWidth = mHeight = 0.0f;
-}
-
 //----------------------------------------------------------------------
 // nsISupports methods:
 
diff --git a/content/svg/content/src/nsSVGRect.h b/content/svg/content/src/nsSVGRect.h
index 883cf9bf6346..e44510d8a30a 100644
--- a/content/svg/content/src/nsSVGRect.h
+++ b/content/svg/content/src/nsSVGRect.h
@@ -41,9 +41,10 @@
 #define __NS_SVGRECT_H__
 
 #include "nsIDOMSVGRect.h"
-#include "nsSVGValue.h"
 #include "gfxRect.h"
 
+class nsIDOMSVGLength;
+
 nsresult
 NS_NewSVGRect(nsIDOMSVGRect** result,
               float x=0.0f, float y=0.0f,
@@ -57,29 +58,4 @@ NS_NewSVGReadonlyRect(nsIDOMSVGRect** result,
                       float x=0.0f, float y=0.0f,
                       float width=0.0f, float height=0.0f);
 
-////////////////////////////////////////////////////////////////////////
-// nsSVGRect class
-
-class nsSVGRect : public nsIDOMSVGRect,
-                  public nsSVGValue
-{
-public:
-  nsSVGRect(float x=0.0f, float y=0.0f, float w=0.0f, float h=0.0f);
-
-  // nsISupports interface:
-  NS_DECL_ISUPPORTS
-
-  // nsIDOMSVGRect interface:
-  NS_DECL_NSIDOMSVGRECT
-
-  // nsISVGValue interface:
-  NS_IMETHOD SetValueString(const nsAString& aValue);
-  NS_IMETHOD GetValueString(nsAString& aValue);
-
-  void Clear();
-
-protected:
-  float mX, mY, mWidth, mHeight;
-};
-
 #endif //__NS_SVGRECT_H__