DOMException toString is not correct

LayoutTests/fast/dom/Range/compareBoundaryPoints-1.html

 <p>This tests to see that Range::compareBoundaryPoints throws a WrongDocumentError exception if the two ranges are in different documents, or if one is detached.</p>
 <div id="div" contenteditable="true">dog<a href="http://www.google.com/">food</a></div>
 <ul id="console"></ul>
 
 <script>
 function log(str) {
     var console = document.getElementById("console");
     var li = document.createElement("li");
     li.appendChild(document.createTextNode(str));
     console.appendChild(li);
@@ skipping 14 matching lines @@
 r1.setEnd(link, 0);
 
 var r2 = document.createRange();
 r2.setStart(text, 0);
 r2.setEnd(text, 0);
 
 try {
     var compare = r1.compareBoundaryPoints(Range.START_TO_START, r2);
     log("Error.  compareBoundaryPoints should have thrown an exception.");
 } catch (e) {
-    var expected = "Error: WrongDocumentError: DOM Exception 4";
+    var expected = "WrongDocumentError: A Node was used in a different document than the one that created it (that doesn't support it).";
     if (e != expected)
         log("Error.  Exception thrown should have been: " + expected);
 }
 </script>