diff --git a/dom/tests/mochitest/bugs/Makefile.in b/dom/tests/mochitest/bugs/Makefile.in
index 6f39e72957ef..62eaf858addc 100644
--- a/dom/tests/mochitest/bugs/Makefile.in
+++ b/dom/tests/mochitest/bugs/Makefile.in
@@ -144,6 +144,7 @@ _TEST_FILES	= \
 		test_bug648465.html \
 		test_bug654137.html \
 		test_bug684544.html \
+		test_bug698551.html \
 		test_window_bar.html \
 		file_window_bar.html \
 		test_resize_move_windows.html \
diff --git a/dom/tests/mochitest/bugs/test_bug698551.html b/dom/tests/mochitest/bugs/test_bug698551.html
new file mode 100644
index 000000000000..70a002bb97b9
--- /dev/null
+++ b/dom/tests/mochitest/bugs/test_bug698551.html
@@ -0,0 +1,39 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=698551
+-->
+<head>
+  <title>Test for Bug 698551</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=698551">Mozilla Bug 698551</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+  
+</div>
+<pre id="test">
+<script type="application/javascript">
+
+/** Test for Bug 698551 **/
+var l = document.getElementsByTagName("body");
+var it = Object.getPrototypeOf(l).item;
+Object.defineProperty(Object.getPrototypeOf(l), "item",
+{
+  get: function() { return it; },
+});
+Object.defineProperty(Object.getPrototypeOf(l), "foopy",
+{
+  get: function() { return this[0]; },
+});
+is(l.foopy, document.body,
+   "Should end up with the body correctly when getting via [0]");
+is(l.item(0), document.body,
+   "Should end up with the body correctly when getting via .item(0)");
+is(l.length, 1, "Should have one body");
+</script>
+</pre>
+</body>
+</html>
diff --git a/js/src/jsapi.cpp b/js/src/jsapi.cpp
index 0c670ffe01b1..1f1ef983e993 100644
--- a/js/src/jsapi.cpp
+++ b/js/src/jsapi.cpp
@@ -3833,11 +3833,18 @@ JS_SetUCPropertyAttributes(JSContext *cx, JSObject *obj, const jschar *name, siz
 
 JS_PUBLIC_API(JSBool)
 JS_GetPropertyById(JSContext *cx, JSObject *obj, jsid id, jsval *vp)
+{
+    return JS_ForwardGetPropertyTo(cx, obj, id, obj, vp);
+}
+
+JS_PUBLIC_API(JSBool)
+JS_ForwardGetPropertyTo(JSContext *cx, JSObject *obj, jsid id, JSObject *onBehalfOf, jsval *vp)
 {
     CHECK_REQUEST(cx);
     assertSameCompartment(cx, obj, id);
+    assertSameCompartment(cx, onBehalfOf);
     JSAutoResolveFlags rf(cx, JSRESOLVE_QUALIFIED);
-    return obj->getGeneric(cx, id, vp);
+    return obj->getGeneric(cx, onBehalfOf, id, vp);
 }
 
 JS_PUBLIC_API(JSBool)
@@ -3848,12 +3855,17 @@ JS_GetPropertyByIdDefault(JSContext *cx, JSObject *obj, jsid id, jsval def, jsva
 
 JS_PUBLIC_API(JSBool)
 JS_GetElement(JSContext *cx, JSObject *obj, uint32 index, jsval *vp)
+{
+    return JS_ForwardGetElementTo(cx, obj, index, obj, vp);
+}
+
+JS_PUBLIC_API(JSBool)
+JS_ForwardGetElementTo(JSContext *cx, JSObject *obj, uint32 index, JSObject *onBehalfOf, jsval *vp)
 {
     CHECK_REQUEST(cx);
-    jsid id;
-    if (!IndexToId(cx, index, &id))
-        return false;
-    return JS_GetPropertyById(cx, obj, id, vp);
+    assertSameCompartment(cx, obj);
+    JSAutoResolveFlags rf(cx, JSRESOLVE_QUALIFIED);
+    return obj->getElement(cx, onBehalfOf, index, vp);
 }
 
 JS_PUBLIC_API(JSBool)
@@ -3909,10 +3921,9 @@ JS_PUBLIC_API(JSBool)
 JS_SetElement(JSContext *cx, JSObject *obj, uint32 index, jsval *vp)
 {
     CHECK_REQUEST(cx);
-    jsid id;
-    if (!IndexToId(cx, index, &id))
-        return false;
-    return JS_SetPropertyById(cx, obj, INT_TO_JSID(index), vp);
+    assertSameCompartment(cx, obj);
+    JSAutoResolveFlags rf(cx, JSRESOLVE_QUALIFIED | JSRESOLVE_ASSIGNING);
+    return obj->setElement(cx, index, vp, false);
 }
 
 JS_PUBLIC_API(JSBool)
diff --git a/js/src/jsapi.h b/js/src/jsapi.h
index f004601d852d..9641cf841a08 100644
--- a/js/src/jsapi.h
+++ b/js/src/jsapi.h
@@ -3431,6 +3431,9 @@ JS_GetPropertyById(JSContext *cx, JSObject *obj, jsid id, jsval *vp);
 extern JS_PUBLIC_API(JSBool)
 JS_GetPropertyByIdDefault(JSContext *cx, JSObject *obj, jsid id, jsval def, jsval *vp);
 
+extern JS_PUBLIC_API(JSBool)
+JS_ForwardGetPropertyTo(JSContext *cx, JSObject *obj, jsid id, JSObject *onBehalfOf, jsval *vp);
+
 extern JS_PUBLIC_API(JSBool)
 JS_GetMethodById(JSContext *cx, JSObject *obj, jsid id, JSObject **objp,
                  jsval *vp);
@@ -3563,6 +3566,9 @@ JS_LookupElement(JSContext *cx, JSObject *obj, uint32 index, jsval *vp);
 extern JS_PUBLIC_API(JSBool)
 JS_GetElement(JSContext *cx, JSObject *obj, uint32 index, jsval *vp);
 
+extern JS_PUBLIC_API(JSBool)
+JS_ForwardGetElementTo(JSContext *cx, JSObject *obj, uint32 index, JSObject *onBehalfOf, jsval *vp);
+
 extern JS_PUBLIC_API(JSBool)
 JS_SetElement(JSContext *cx, JSObject *obj, uint32 index, jsval *vp);
 
diff --git a/js/xpconnect/src/dombindings.cpp b/js/xpconnect/src/dombindings.cpp
index b1f38681622b..55f120594e90 100644
--- a/js/xpconnect/src/dombindings.cpp
+++ b/js/xpconnect/src/dombindings.cpp
@@ -975,7 +975,7 @@ ListBase<LC>::getPropertyOnPrototype(JSContext *cx, JSObject *proxy, jsid id, bo
     if (!hasProp || !vp)
         return true;
 
-    return JS_GetPropertyById(cx, proto, id, vp);
+    return JS_ForwardGetPropertyTo(cx, proto, id, proxy, vp);
 }
 
 template<class LC>
