--- a/js/jsd/jsd.h
+++ b/js/jsd/jsd.h
@@ -967,16 +967,19 @@ extern jsdouble
 jsd_GetValueDouble(JSDContext* jsdc, JSDValue* jsdval);
 
 extern JSString*
 jsd_GetValueString(JSDContext* jsdc, JSDValue* jsdval);
 
 extern JSString*
 jsd_GetValueFunctionName(JSDContext* jsdc, JSDValue* jsdval);
 
+extern JSFunction*
+jsd_GetValueFunction(JSDContext* jsdc, JSDValue* jsdval);
+
 /**************************************************/
 
 extern uintN
 jsd_GetCountOfProperties(JSDContext* jsdc, JSDValue* jsdval);
 
 extern JSDProperty*
 jsd_IterateProperties(JSDContext* jsdc, JSDValue* jsdval, JSDProperty **iterp);
 

--- a/js/jsd/jsd_val.c
+++ b/js/jsd/jsd_val.c
@@ -137,50 +137,49 @@ jsd_IsValuePrimitive(JSDContext* jsdc, J
 {
     return JSVAL_IS_PRIMITIVE(jsdval->val);
 }
 
 JSBool
 jsd_IsValueFunction(JSDContext* jsdc, JSDValue* jsdval)
 {
     return !JSVAL_IS_PRIMITIVE(jsdval->val) &&
-           JS_ObjectIsFunction(jsdc->dumbContext, JSVAL_TO_OBJECT(jsdval->val));
+           JS_ObjectIsCallable(jsdc->dumbContext, JSVAL_TO_OBJECT(jsdval->val));
 }
 
 JSBool
 jsd_IsValueNative(JSDContext* jsdc, JSDValue* jsdval)
 {
     JSContext* cx = jsdc->dumbContext;
-    jsval val = jsdval->val;
     JSFunction* fun;
     JSExceptionState* exceptionState;
     JSCrossCompartmentCall *call = NULL;
 
     if(jsd_IsValueFunction(jsdc, jsdval))
     {
         JSBool ok = JS_FALSE;
         JS_BeginRequest(cx);
-        call = JS_EnterCrossCompartmentCall(jsdc->dumbContext, JSVAL_TO_OBJECT(val));
+        call = JS_EnterCrossCompartmentCall(jsdc->dumbContext, JSVAL_TO_OBJECT(jsdval->val));
         if(!call) {
             JS_EndRequest(cx);
 
             return JS_FALSE;
         }
 
         exceptionState = JS_SaveExceptionState(cx);
-        fun = JS_ValueToFunction(cx, val);
+        fun = JSD_GetValueFunction(jsdc, jsdval);
         JS_RestoreExceptionState(cx, exceptionState);
         if(fun)
             ok = JS_GetFunctionScript(cx, fun) ? JS_FALSE : JS_TRUE;
         JS_LeaveCrossCompartmentCall(call);
         JS_EndRequest(cx);
         JS_ASSERT(fun);
         return ok;
     }
-    return !JSVAL_IS_PRIMITIVE(val);
+    return !JSVAL_IS_PRIMITIVE(jsdval->val);
 }
 
 /***************************************************************************/
 
 JSBool
 jsd_GetValueBoolean(JSDContext* jsdc, JSDValue* jsdval)
 {
     jsval val = jsdval->val;
@@ -260,17 +259,17 @@ jsd_GetValueFunctionName(JSDContext* jsd
         call = JS_EnterCrossCompartmentCall(jsdc->dumbContext, JSVAL_TO_OBJECT(jsdval->val));
         if(!call) {
             JS_EndRequest(cx);
 
             return NULL;
         }
 
         exceptionState = JS_SaveExceptionState(cx);
-        fun = JS_ValueToFunction(cx, jsdval->val);
+        fun = JSD_GetValueFunction(jsdc, jsdval);
         JS_RestoreExceptionState(cx, exceptionState);
         JS_LeaveCrossCompartmentCall(call);
         JS_EndRequest(cx);
         if(!fun)
             return NULL;
         jsdval->funName = JS_GetFunctionId(fun);
 
         /* For compatibility we return "anonymous", not an empty string here. */
@@ -632,16 +631,40 @@ jsd_GetValueProperty(JSDContext* jsdc, J
     pd.alias = JSVAL_NULL;
     pd.flags |= (attrs & JSPROP_ENUMERATE) ? JSPD_ENUMERATE : 0
         | (attrs & JSPROP_READONLY)  ? JSPD_READONLY  : 0
         | (attrs & JSPROP_PERMANENT) ? JSPD_PERMANENT : 0;
 
     return _newProperty(jsdc, &pd, JSDPD_HINTED);
 }
 
+/*
+ * Retrieve a JSFunction* from a JSDValue*. This differs from
+ * JS_ValueToFunction by fully unwrapping the object first.
+ */
+JSFunction*
+jsd_GetValueFunction(JSDContext* jsdc, JSDValue* jsdval)
+{
+    JSObject *obj;
+    JSFunction *fun;
+    JSCrossCompartmentCall *call = NULL;
+    if (!JSVAL_IS_OBJECT(jsdval->val))
+        return NULL;
+    if(!(obj = JSVAL_TO_OBJECT(jsdval->val)))
+        return NULL;
+    obj = JS_UnwrapObject(jsdc->dumbContext, obj);
+
+    call = JS_EnterCrossCompartmentCall(jsdc->dumbContext, obj);
+    if (!call)
+        return NULL;
+    fun = JS_ValueToFunction(jsdc->dumbContext, OBJECT_TO_JSVAL(obj));
+    JS_LeaveCrossCompartmentCall(call);
+
+    return fun;
+}
 
 JSDValue*
 jsd_GetValuePrototype(JSDContext* jsdc, JSDValue* jsdval)
 {
     JSCrossCompartmentCall *call = NULL;
 
     if(!(CHECK_BIT_FLAG(jsdval->flags, GOT_PROTO)))
     {
@@ -792,17 +815,17 @@ jsd_GetScriptForValue(JSDContext* jsdc, 
     call = JS_EnterCrossCompartmentCall(cx, JSVAL_TO_OBJECT(val));
     if (!call) {
         JS_EndRequest(cx);
 
         return NULL;
     }
 
     exceptionState = JS_SaveExceptionState(cx);
-    fun = JS_ValueToFunction(cx, val);
+    fun = JSD_GetValueFunction(jsdc, jsdval);
     JS_RestoreExceptionState(cx, exceptionState);
     if (fun)
         script = JS_GetFunctionScript(cx, fun);
     JS_LeaveCrossCompartmentCall(call);
     JS_EndRequest(cx);
 
     if (!script)
         return NULL;

--- a/js/jsd/jsdebug.c
+++ b/js/jsd/jsdebug.c
@@ -1119,16 +1119,24 @@ JSD_GetValueString(JSDContext* jsdc, JSD
 JSD_PUBLIC_API(JSString *)
 JSD_GetValueFunctionName(JSDContext* jsdc, JSDValue* jsdval)
 {
     JSD_ASSERT_VALID_CONTEXT(jsdc);
     JSD_ASSERT_VALID_VALUE(jsdval);
     return jsd_GetValueFunctionName(jsdc, jsdval);
 }
 
+JSD_PUBLIC_API(JSFunction*)
+JSD_GetValueFunction(JSDContext* jsdc, JSDValue* jsdval)
+{
+    JSD_ASSERT_VALID_CONTEXT(jsdc);
+    JSD_ASSERT_VALID_VALUE(jsdval);
+    return jsd_GetValueFunction(jsdc, jsdval);
+}
+
 /**************************************************/
 
 JSD_PUBLIC_API(uintN)
 JSD_GetCountOfProperties(JSDContext* jsdc, JSDValue* jsdval)
 {
     JSD_ASSERT_VALID_CONTEXT(jsdc);
     JSD_ASSERT_VALID_VALUE(jsdval);
     return jsd_GetCountOfProperties(jsdc, jsdval);

--- a/js/jsd/jsdebug.h
+++ b/js/jsd/jsdebug.h
@@ -1293,16 +1293,24 @@ JSD_GetValueString(JSDContext* jsdc, JSD
 
 /*
 * Return name of function IFF JSDValue represents a function.
 * *** new for version 1.1 ****
 */
 extern JSD_PUBLIC_API(JSString *)
 JSD_GetValueFunctionName(JSDContext* jsdc, JSDValue* jsdval);
 
+/*
+* Return function object IFF JSDValue represents a function or an object
+* wrapping a function.
+* *** new for version 1.1 ****
+*/
+extern JSD_PUBLIC_API(JSFunction*)
+JSD_GetValueFunction(JSDContext* jsdc, JSDValue* jsdval);
+
 /**************************************************/
 
 /*
 * Return the number of properties for the JSDValue.
 * *** new for version 1.1 ****
 */
 extern JSD_PUBLIC_API(uintN)
 JSD_GetCountOfProperties(JSDContext* jsdc, JSDValue* jsdval);

--- a/js/src/jsapi.cpp
+++ b/js/src/jsapi.cpp
@@ -4225,16 +4225,22 @@ JS_GetFunctionArity(JSFunction *fun)
 }
 
 JS_PUBLIC_API(JSBool)
 JS_ObjectIsFunction(JSContext *cx, JSObject *obj)
 {
     return obj->getClass() == &js_FunctionClass;
 }
 
+JS_PUBLIC_API(JSBool)
+JS_ObjectIsCallable(JSContext *cx, JSObject *obj)
+{
+    return obj->isCallable();
+}
+
 static JSBool
 js_generic_native_method_dispatcher(JSContext *cx, uintN argc, Value *vp)
 {
     JSFunctionSpec *fs;
     JSObject *tmp;
     Native native;
 
     fs = (JSFunctionSpec *) vp->toObject().getReservedSlot(0).toPrivate();

--- a/js/src/jsapi.h
+++ b/js/src/jsapi.h
@@ -2572,16 +2572,19 @@ JS_GetFunctionArity(JSFunction *fun);
  * comparing obj's class name to "Function", but equivalent unless someone has
  * overwritten the "Function" identifier with a different constructor and then
  * created instances using that constructor that might be passed in as obj).
  */
 extern JS_PUBLIC_API(JSBool)
 JS_ObjectIsFunction(JSContext *cx, JSObject *obj);
 
 extern JS_PUBLIC_API(JSBool)
+JS_ObjectIsCallable(JSContext *cx, JSObject *obj);
+
+extern JS_PUBLIC_API(JSBool)
 JS_DefineFunctions(JSContext *cx, JSObject *obj, JSFunctionSpec *fs);
 
 extern JS_PUBLIC_API(JSFunction *)
 JS_DefineFunction(JSContext *cx, JSObject *obj, const char *name, JSNative call,
                   uintN nargs, uintN attrs);
 
 extern JS_PUBLIC_API(JSFunction *)
 JS_DefineUCFunction(JSContext *cx, JSObject *obj,

--- a/js/src/jsdbgapi.cpp
+++ b/js/src/jsdbgapi.cpp
@@ -1856,16 +1856,24 @@ JS_PUBLIC_API(JSBool)
 JS_MakeSystemObject(JSContext *cx, JSObject *obj)
 {
     obj->setSystem();
     return true;
 }
 
 /************************************************************************/
 
+JS_PUBLIC_API(JSObject *)
+JS_UnwrapObject(JSContext *cx, JSObject *obj)
+{
+    return obj->unwrap();
+}
+
+/************************************************************************/
+
 JS_FRIEND_API(void)
 js_RevertVersion(JSContext *cx)
 {
     cx->clearVersionOverride();
 }
 
 JS_PUBLIC_API(const JSDebugHooks *)
 JS_GetGlobalDebugHooks(JSRuntime *rt)

--- a/js/src/jsdbgapi.h
+++ b/js/src/jsdbgapi.h
@@ -482,16 +482,21 @@ JS_IsSystemObject(JSContext *cx, JSObjec
  * after allocating the object. A system object is an object for which
  * JS_IsSystemObject returns true.
  */
 extern JS_PUBLIC_API(JSBool)
 JS_MakeSystemObject(JSContext *cx, JSObject *obj);
 
 /************************************************************************/
 
+extern JS_PUBLIC_API(JSObject *)
+JS_UnwrapObject(JSContext *cx, JSObject *obj);
+
+/************************************************************************/
+
 extern JS_FRIEND_API(void)
 js_RevertVersion(JSContext *cx);
 
 extern JS_PUBLIC_API(const JSDebugHooks *)
 JS_GetGlobalDebugHooks(JSRuntime *rt);
 
 extern JS_PUBLIC_API(JSDebugHooks *)
 JS_SetContextDebugHooks(JSContext *cx, const JSDebugHooks *hooks);