Java Plugin 1.6.0_12 .pac file regex on Windows XP

The following works fine in IE when the plugin is not involved. When the Java Plugin 1.6.0u12 parses the .pac file, it fails.

The Java Plug-in fails to parse an automatic proxy configuration script if a regular expression is defined which ends with a slash.
(environment: Windows XP, Java 6.0 update12)

To reproduce:
- Define in the browser settings an automatic proxy configuration script which contains the following code:
   var regex = /a.*\//
   if (regex.test("a1/")) {
     return "PROXY host1:80";
   }
   return "PROXY host2:80";
- Configure the Java Plug-in to use the browser settings (as network settings)
- Try to download an HTML page which includes an applet.
- The Java console shows:
network: Unable to determine proxy setting from evaluation - fallback to DIRECT
- If the regular expression does not end with a slash, the problem does not occur, for example:
var regex = /a.*/