diff --git a/lib/OpenLayers.js b/lib/OpenLayers.js
index e755788845..29f964cf22 100644
--- a/lib/OpenLayers.js
+++ b/lib/OpenLayers.js
@@ -37,28 +37,22 @@
          * {String} Path to this script
          */
         _getScriptLocation: function () {
-            var scriptLocation = "";
-            var scriptName = OpenLayers._scriptName;
+            var scriptLocation = "";            
+            var isOL = new RegExp("(^|(.*?\\/))(" + OpenLayers._scriptName + ")(\\?|$)");
          
             var scripts = document.getElementsByTagName('script');
             for (var i=0, len=scripts.length; i<len; i++) {
                 var src = scripts[i].getAttribute('src');
                 if (src) {
-                    var index = src.lastIndexOf(scriptName); 
-                    // set path length for src up to a query string
-                    var pathLength = src.lastIndexOf('?');
-                    if (pathLength < 0) {
-                        pathLength = src.length;
-                    }
-                    // is it found, at the end of the URL?
-                    if ((index > -1) && (index + scriptName.length == pathLength)) {
-                        scriptLocation = src.slice(0, pathLength - scriptName.length);
+                    var match = src.match(isOL);
+                    if(match) {
+                        scriptLocation = match[1];
                         break;
                     }
                 }
             }
             return scriptLocation;
-         }
+        }
     };
     /**
      * OpenLayers.singleFile is a flag indicating this file is being included
diff --git a/tests/OpenLayers.html b/tests/OpenLayers.html
index 947d3c6598..89081d7983 100644
--- a/tests/OpenLayers.html
+++ b/tests/OpenLayers.html
@@ -1,19 +1,24 @@
 <html>
 <head>
-  <script id="script" src="../lib/OpenLayers.js"></script>
-  <script type="text/javascript">
-    function test_OpenLayers(t) {
-        t.plan(2);
-        
-        var script = document.getElementById("script");
+    <script src="bogus/1/OpenLayers.js-foo"></script>
+    <script src="bogus/2/foo-OpenLayers.js"></script>
+    <script id="script" src="../lib/OpenLayers.js"></script>
+    <script type="text/javascript">
+        function test_OpenLayers(t) {
+            t.plan(3);
 
-        t.eq(OpenLayers._getScriptLocation(), "../", "Script location correctly detected.");
-        
-        script.setAttribute("src", "../lib/OpenLayers.js?foo");
-        t.eq(OpenLayers._getScriptLocation(), "../", "Script location with search string correctly detected.");
-    }
+            var script = document.getElementById("script");
 
-  </script>
+            t.eq(OpenLayers._getScriptLocation(), "../", "Script location correctly detected.");
+            script.setAttribute("src", "../lib/OpenLayers.js?foo");
+            t.eq(OpenLayers._getScriptLocation(), "../", "Script location with search string correctly detected.");
+
+            // now pretend we're using a built script
+            OpenLayers._scriptName = "OpenLayers.js";
+            t.eq(OpenLayers._getScriptLocation(), "../lib/", "not fooled by bogus paths");
+            
+        }
+    </script>
 </head>
 <body>
 </body>
