diff -r 777bd3ed81ba -r 45c50b9c7dc4 launcher/http/src/main/java/org/apidesign/bck2brwsr/launcher/Bck2BrwsrLauncher.java
--- a/launcher/http/src/main/java/org/apidesign/bck2brwsr/launcher/Bck2BrwsrLauncher.java	Mon May 05 10:16:30 2014 +0200
+++ b/launcher/http/src/main/java/org/apidesign/bck2brwsr/launcher/Bck2BrwsrLauncher.java	Mon May 05 13:49:05 2014 +0200
@@ -95,11 +95,12 @@
         sb.append(
               "(function WrapperVM(global) {\n"
             + "  var cache = {};\n"
+            + "  var empty = {};\n"
             + "  function ldCls(res, skip) {\n"
             + "    var c = cache[res];\n"
             + "    if (c) {\n"
+            + "      if (c[skip] === empty) return null;\n"
             + "      if (c[skip]) return c[skip];\n"
-            + "      if (c[skip] === null) return null;\n"
             + "    } else {\n"
             + "      cache[res] = c = new Array();\n"
             + "    }\n"
@@ -111,6 +112,7 @@
             + "      return null;\n"
             + "    }\n"
             + "    var arr = eval(request.responseText);\n"
+            + "    if (arr === null) arr = empty;\n"
             + "    c[skip] = arr;\n"
             + "    return arr;\n"
             + "  }\n"