diff --git a/js/xpconnect/src/XPCForwards.h b/js/xpconnect/src/XPCForwards.h
index 08a1c5401ac7..64096a3d6375 100644
--- a/js/xpconnect/src/XPCForwards.h
+++ b/js/xpconnect/src/XPCForwards.h
@@ -81,7 +81,6 @@ class NativeSetMap;
 class IID2ThisTranslatorMap;
 class XPCNativeScriptableSharedMap;
 class XPCWrappedNativeProtoMap;
-class XPCNativeWrapperMap;
 class WrappedNative2WrapperMap;
 class JSObject2JSObjectMap;
 
diff --git a/js/xpconnect/src/XPCJSRuntime.cpp b/js/xpconnect/src/XPCJSRuntime.cpp
index cbfa495cc739..4db7dbc7da11 100644
--- a/js/xpconnect/src/XPCJSRuntime.cpp
+++ b/js/xpconnect/src/XPCJSRuntime.cpp
@@ -1202,15 +1202,6 @@ XPCJSRuntime::~XPCJSRuntime()
         delete mDetachedWrappedNativeProtoMap;
     }
 
-    if (mExplicitNativeWrapperMap) {
-#ifdef XPC_DUMP_AT_SHUTDOWN
-        uint32_t count = mExplicitNativeWrapperMap->Count();
-        if (count)
-            printf("deleting XPCJSRuntime with %d live explicit XPCNativeWrapper\n", (int)count);
-#endif
-        delete mExplicitNativeWrapperMap;
-    }
-
     if (mJSHolders.ops) {
         JS_DHashTableFinish(&mJSHolders);
         mJSHolders.ops = nsnull;
@@ -1961,7 +1952,6 @@ XPCJSRuntime::XPCJSRuntime(nsXPConnect* aXPConnect)
    mNativeScriptableSharedMap(XPCNativeScriptableSharedMap::newMap(XPC_NATIVE_JSCLASS_MAP_SIZE)),
    mDyingWrappedNativeProtoMap(XPCWrappedNativeProtoMap::newMap(XPC_DYING_NATIVE_PROTO_MAP_SIZE)),
    mDetachedWrappedNativeProtoMap(XPCWrappedNativeProtoMap::newMap(XPC_DETACHED_NATIVE_PROTO_MAP_SIZE)),
-   mExplicitNativeWrapperMap(XPCNativeWrapperMap::newMap(XPC_NATIVE_WRAPPER_MAP_SIZE)),
    mMapLock(XPCAutoLock::NewLock("XPCJSRuntime::mMapLock")),
    mThreadRunningGC(nsnull),
    mWrappedJSToReleaseArray(),
@@ -2080,7 +2070,6 @@ XPCJSRuntime::newXPCJSRuntime(nsXPConnect* aXPConnect)
         self->GetThisTranslatorMap()          &&
         self->GetNativeScriptableSharedMap()  &&
         self->GetDyingWrappedNativeProtoMap() &&
-        self->GetExplicitNativeWrapperMap()   &&
         self->GetMapLock()                    &&
         self->mWatchdogThread) {
         return self;
diff --git a/js/xpconnect/src/XPCMaps.cpp b/js/xpconnect/src/XPCMaps.cpp
index 6250604923a4..44969027dfe0 100644
--- a/js/xpconnect/src/XPCMaps.cpp
+++ b/js/xpconnect/src/XPCMaps.cpp
@@ -674,32 +674,6 @@ XPCWrappedNativeProtoMap::~XPCWrappedNativeProtoMap()
         JS_DHashTableDestroy(mTable);
 }
 
-/***************************************************************************/
-// implement XPCNativeWrapperMap...
-
-// static
-XPCNativeWrapperMap*
-XPCNativeWrapperMap::newMap(int size)
-{
-    XPCNativeWrapperMap* map = new XPCNativeWrapperMap(size);
-    if (map && map->mTable)
-        return map;
-    delete map;
-    return nsnull;
-}
-
-XPCNativeWrapperMap::XPCNativeWrapperMap(int size)
-{
-    mTable = JS_NewDHashTable(JS_DHashGetStubOps(), nsnull,
-                              sizeof(JSDHashEntryStub), size);
-}
-
-XPCNativeWrapperMap::~XPCNativeWrapperMap()
-{
-    if (mTable)
-        JS_DHashTableDestroy(mTable);
-}
-
 /***************************************************************************/
 // implement WrappedNative2WrapperMap...
 
diff --git a/js/xpconnect/src/XPCMaps.h b/js/xpconnect/src/XPCMaps.h
index 446c817a0ad0..5c75a0727ae5 100644
--- a/js/xpconnect/src/XPCMaps.h
+++ b/js/xpconnect/src/XPCMaps.h
@@ -635,42 +635,6 @@ private:
     JSDHashTable *mTable;
 };
 
-class XPCNativeWrapperMap
-{
-public:
-    static XPCNativeWrapperMap* newMap(int size);
-
-    inline JSObject* Add(JSObject* nw)
-    {
-        NS_PRECONDITION(nw,"bad param");
-        JSDHashEntryStub* entry = (JSDHashEntryStub*)
-            JS_DHashTableOperate(mTable, nw, JS_DHASH_ADD);
-        if (!entry)
-            return nsnull;
-        if (entry->key)
-            return (JSObject*) entry->key;
-        entry->key = nw;
-        return nw;
-    }
-
-    inline void Remove(JSObject* nw)
-    {
-        NS_PRECONDITION(nw,"bad param");
-        JS_DHashTableOperate(mTable, nw, JS_DHASH_REMOVE);
-    }
-
-    inline uint32_t Count() {return mTable->entryCount;}
-    inline uint32_t Enumerate(JSDHashEnumerator f, void *arg)
-        {return JS_DHashTableEnumerate(mTable, f, arg);}
-
-    ~XPCNativeWrapperMap();
-private:
-    XPCNativeWrapperMap();    // no implementation
-    XPCNativeWrapperMap(int size);
-private:
-    JSDHashTable *mTable;
-};
-
 class WrappedNative2WrapperMap
 {
     static struct JSDHashTableOps sOps;
diff --git a/js/xpconnect/src/xpcprivate.h b/js/xpconnect/src/xpcprivate.h
index fb524bdd96a1..5af27ecd9249 100644
--- a/js/xpconnect/src/xpcprivate.h
+++ b/js/xpconnect/src/xpcprivate.h
@@ -684,9 +684,6 @@ public:
     XPCWrappedNativeProtoMap* GetDetachedWrappedNativeProtoMap() const
         {return mDetachedWrappedNativeProtoMap;}
 
-    XPCNativeWrapperMap* GetExplicitNativeWrapperMap() const
-        {return mExplicitNativeWrapperMap;}
-
     XPCCompartmentMap& GetCompartmentMap()
         {return mCompartmentMap;}
 
@@ -832,7 +829,6 @@ private:
     XPCNativeScriptableSharedMap* mNativeScriptableSharedMap;
     XPCWrappedNativeProtoMap* mDyingWrappedNativeProtoMap;
     XPCWrappedNativeProtoMap* mDetachedWrappedNativeProtoMap;
-    XPCNativeWrapperMap*     mExplicitNativeWrapperMap;
     XPCCompartmentMap        mCompartmentMap;
     XPCLock* mMapLock;
     PRThread* mThreadRunningGC;