diff --git a/js/src/xpconnect/src/XPCDispInlines.h b/js/src/xpconnect/src/XPCDispInlines.h
index beaa0d4a2f2..818cd54fa40 100644
--- a/js/src/xpconnect/src/XPCDispInlines.h
+++ b/js/src/xpconnect/src/XPCDispInlines.h
@@ -108,7 +108,7 @@ VARTYPE XPCDispInterface::Member::ParamInfo::GetType() const
 
 inline
 XPCDispInterface::Member::Member() : 
-    mType(UNINITIALIZED), mFuncDesc(0),
+    mType(UNINITIALIZED), mFuncDesc(0), mGetterFuncDesc(0),
     mTypeInfo(0) 
 {
 }
@@ -116,8 +116,13 @@ XPCDispInterface::Member::Member() :
 inline
 XPCDispInterface::Member::~Member() 
 {
-    if(mTypeInfo && mFuncDesc) 
-        mTypeInfo->ReleaseFuncDesc(mFuncDesc);
+    if(mTypeInfo)
+    {
+        if (mFuncDesc) 
+            mTypeInfo->ReleaseFuncDesc(mFuncDesc);
+        if (mGetterFuncDesc)
+            mTypeInfo->ReleaseFuncDesc(mGetterFuncDesc);
+    }
 }
 
 inline
@@ -183,10 +188,23 @@ PRBool XPCDispInterface::Member::IsFunction() const
     return IsFlagSet(FUNCTION);
 }
 
+inline
+PRBool XPCDispInterface::Member::IsParameterizedSetter() const
+{
+    return IsSetter() && GetParamCount() > 1;
+}
+
+inline
+PRBool XPCDispInterface::Member::IsParameterizedGetter() const
+{
+    return IsGetter() && (GetParamCount(PR_TRUE) > 1 ||
+        (GetParamCount(PR_TRUE) == 1 && GetParamInfo(0, PR_TRUE).IsRetVal()));
+}
+
 inline
 PRBool XPCDispInterface::Member::IsParameterizedProperty() const
 {
-    return (IsSetter() && GetParamCount() > 1) || (IsGetter() && GetParamCount() > 0);
+    return IsParameterizedSetter() || IsParameterizedGetter();
 }
 
 inline
@@ -208,16 +226,16 @@ PRUint32 XPCDispInterface::Member::GetDispID() const
 }
 
 inline
-PRUint32 XPCDispInterface::Member::GetParamCount() const
+PRUint32 XPCDispInterface::Member::GetParamCount(PRBool getter) const
 {
-    return mFuncDesc->cParams;
+    return (getter && mGetterFuncDesc) ? mGetterFuncDesc->cParams : mFuncDesc->cParams;
 }
 
 inline
-XPCDispInterface::Member::ParamInfo XPCDispInterface::Member::GetParamInfo(PRUint32 index) 
+XPCDispInterface::Member::ParamInfo XPCDispInterface::Member::GetParamInfo(PRUint32 index, PRBool getter) const
 {
-    NS_ASSERTION(index < GetParamCount(), "Array bounds error");
-    return ParamInfo(mFuncDesc->lprgelemdescParam + index);
+    NS_ASSERTION(index < GetParamCount(getter), "Array bounds error");
+    return ParamInfo(((getter && mGetterFuncDesc) ? mGetterFuncDesc->lprgelemdescParam : mFuncDesc->lprgelemdescParam) + index);
 }
 
 inline
@@ -229,6 +247,12 @@ void XPCDispInterface::Member::SetTypeInfo(DISPID dispID,
     mFuncDesc = funcdesc;
 }
 
+inline
+void XPCDispInterface::Member::SetGetterFuncDesc(FUNCDESC* funcdesc)
+{
+    mGetterFuncDesc = funcdesc;
+}
+
 inline
 PRUint16 XPCDispInterface::Member::GetParamType(PRUint32 index) const 
 {
diff --git a/js/src/xpconnect/src/XPCDispInterface.cpp b/js/src/xpconnect/src/XPCDispInterface.cpp
index 401e6259bfd..821b0d9e005 100644
--- a/js/src/xpconnect/src/XPCDispInterface.cpp
+++ b/js/src/xpconnect/src/XPCDispInterface.cpp
@@ -189,7 +189,10 @@ PRBool XPCDispInterface::InspectIDispatch(JSContext * cx, ITypeInfo * pTypeInfo,
                 // property
                 else
                 {
-                    ConvertInvokeKind(pFuncDesc->invkind, *(pInfo - 1));
+                    XPCDispInterface::Member * lastInfo = pInfo - 1;
+                    ConvertInvokeKind(pFuncDesc->invkind, *lastInfo);
+                    lastInfo->SetGetterFuncDesc(pFuncDesc);
+                    release = PR_FALSE;
                 }
             }
             if(release)
diff --git a/js/src/xpconnect/src/XPCDispPrivate.h b/js/src/xpconnect/src/XPCDispPrivate.h
index 2630a7c5c90..d0c6286f8b2 100644
--- a/js/src/xpconnect/src/XPCDispPrivate.h
+++ b/js/src/xpconnect/src/XPCDispPrivate.h
@@ -771,6 +771,16 @@ public:
          * @return true if this is a property
          */
         PRBool IsProperty() const;
+        /**
+         * Is this a parameterized setter
+         * @return true if this is a parameterized property
+         */
+        PRBool IsParameterizedSetter() const;
+        /**
+         * Is this a parameterized getter
+         * @return true if this is a parameterized property
+         */
+        PRBool IsParameterizedGetter() const;
         /**
          * Is this a parameterized property
          * @return true if this is a parameterized property
@@ -802,15 +812,17 @@ public:
         PRUint32 GetDispID() const;
         /**
          * returns the number of parameters of the method
+         * @param Ask from getter instead of setter version of the function
          * @return the number of parameters of the method
          */
-        PRUint32 GetParamCount() const;
+        PRUint32 GetParamCount(PRBool getter = PR_FALSE) const;
         /**
          * Returns parameter information for the specified parameter
          * @param index the index of the parameter
+         * @param Ask from getter instead of setter version of the function
          * @return Parameter information
          */
-        ParamInfo GetParamInfo(PRUint32 index);
+        ParamInfo GetParamInfo(PRUint32 index, PRBool getter = PR_FALSE) const;
         // === Setup functions ===
         /**
          * Sets the name of the method
@@ -843,6 +855,12 @@ public:
          */ 
         void SetTypeInfo(DISPID dispID, ITypeInfo* pTypeInfo,
                          FUNCDESC* funcdesc);
+        /**
+         * Sets the function description for the getter version of the function.
+         * @param funcdesc function description
+         */
+        void SetGetterFuncDesc(FUNCDESC* funcdesc);
+
     private:
         /**
          * Our internal flags identify the type of member
@@ -860,7 +878,9 @@ public:
         jsval mVal;     // Mutable
         jsval mName;    // Mutable
         CComPtr<ITypeInfo> mTypeInfo;
-        FUNCDESC* mFuncDesc; // We keep hold on this so we don't have 
+        FUNCDESC* mFuncDesc;         // We own this, and must release it
+        FUNCDESC* mGetterFuncDesc;   // We own this, and must release it
+                                     // This may be the same as mFuncDesc
         /**
          * Helper function to return the parameter type
          * @param index index of the parameter to return the type of