diff -r f18b7262fe91 -r f78cdceed17b launcher/fx/src/main/java/org/apidesign/bck2brwsr/launcher/fximpl/JVMBridge.java
--- a/launcher/fx/src/main/java/org/apidesign/bck2brwsr/launcher/fximpl/JVMBridge.java	Sun Apr 28 17:42:49 2013 +0200
+++ b/launcher/fx/src/main/java/org/apidesign/bck2brwsr/launcher/fximpl/JVMBridge.java	Wed Jun 12 18:19:29 2013 +0200
@@ -17,16 +17,27 @@
  */
 package org.apidesign.bck2brwsr.launcher.fximpl;
 
+import java.net.URL;
 import java.util.TooManyListenersException;
 import javafx.beans.value.ChangeListener;
+import javafx.scene.web.WebEngine;
+import netscape.javascript.JSObject;
 
 /**
  *
  * @author Jaroslav Tulach <jtulach@netbeans.org>
  */
 public final class JVMBridge {
+    private final WebEngine engine;
+    private final WebClassLoader cl;
+    
     private static ClassLoader[] ldrs;
     private static ChangeListener<Void> onBck2BrwsrLoad;
+    
+    JVMBridge(WebEngine eng) {
+        this.engine = eng;
+        this.cl = new WebClassLoader(JVMBridge.class.getClassLoader());
+    }
         
     public static void registerClassLoaders(ClassLoader[] loaders) {
         ldrs = loaders.clone();
@@ -47,18 +58,57 @@
     }
     
     public Class<?> loadClass(String name) throws ClassNotFoundException {
-        System.err.println("trying to load " + name);
-        ClassNotFoundException ex = null;
-        if (ldrs != null) for (ClassLoader l : ldrs) {
-            try {
-                return Class.forName(name, true, l);
-            } catch (ClassNotFoundException ex2) {
-                ex = ex2;
+        return Class.forName(name, true, cl);
+    }
+    
+    private final class WebClassLoader extends JsClassLoader {
+        public WebClassLoader(ClassLoader parent) {
+            super(parent);
+        }
+
+        @Override
+        protected URL findResource(String name) {
+            if (ldrs != null) for (ClassLoader l : ldrs) {
+                URL u = l.getResource(name);
+                if (u != null) {
+                    return u;
+                }
             }
+            return null;
         }
-        if (ex == null) {
-            ex = new ClassNotFoundException("No loaders");
+
+        @Override
+        protected Fn defineFn(String code, String... names) {
+            StringBuilder sb = new StringBuilder();
+            sb.append("(function() {");
+            sb.append("  var x = {};");
+            sb.append("  x.fn = function(");
+            String sep = "";
+            for (String n : names) {
+                sb.append(sep).append(n);
+                sep = ",";
+            }
+            sb.append(") {\n");
+            sb.append(code);
+            sb.append("};");
+            sb.append("return x;");
+            sb.append("})()");
+            
+            JSObject x = (JSObject) engine.executeScript(sb.toString());
+            return new JSFn(x);
         }
-        throw ex;
+    }
+    
+    private static final class JSFn extends Fn {
+        private final JSObject fn;
+
+        public JSFn(JSObject fn) {
+            this.fn = fn;
+        }
+        
+        @Override
+        public Object invoke(Object... args) throws Exception {
+            return fn.call("fn", args); // NOI18N
+        }
     }
 }