diff -r ae352b763959 -r a758763f8415 launcher/src/main/java/org/apidesign/bck2brwsr/launcher/Bck2BrwsrLauncher.java
--- a/launcher/src/main/java/org/apidesign/bck2brwsr/launcher/Bck2BrwsrLauncher.java	Fri Feb 15 21:14:49 2013 +0100
+++ b/launcher/src/main/java/org/apidesign/bck2brwsr/launcher/Bck2BrwsrLauncher.java	Mon Feb 18 19:41:30 2013 +0100
@@ -313,9 +313,13 @@
                 int cnt = is.read() - '0';
                 if (cnt == 'U' - '0') {
                     os.write(baseURL.getBytes("UTF-8"));
-                }
-                if (cnt >= 0 && cnt < params.length) {
-                    os.write(params[cnt].getBytes("UTF-8"));
+                } else {
+                    if (cnt >= 0 && cnt < params.length) {
+                        os.write(params[cnt].getBytes("UTF-8"));
+                    } else {
+                        os.write('$');
+                        os.write(cnt + '0');
+                    }
                 }
             } else {
                 os.write(ch);