A DESCRIPTION OF THE REGRESSION :
Java Web Start 1.6.0-beta
Using JRE version 1.6.0-beta Java HotSpot(TM) Client VM

This code works in production:

String PATH_HELPROOT="com/agris/apps/binmgmt/gui/help/!SSL!/JavaHelp/System_Help.hs";
            ClassLoader cl = HelpUtil.class.getClassLoader();
            URL url = cl.getResource(PATH_HELPROOT);
            helpSet = new HelpSet(cl, url);

I think the exclamation points in the path are causing problems. This is an artifact of some design tool (robohelp, perhaps). A 3rd party manages our help content.

REPRODUCIBLE TESTCASE OR STEPS TO REPRODUCE:
String PATH_HELPROOT="com/agris/apps/binmgmt/gui/help/!SSL!/JavaHelp/System_Help.hs";
            ClassLoader cl = HelpUtil.class.getClassLoader();
            URL url = cl.getResource(PATH_HELPROOT);
            helpSet = new HelpSet(cl, url);



RELEASE LAST WORKED:
5.0

RELEASE TEST FAILS:
mustang-beta

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I expect to get an instance of HelpSet.


ACTUAL -
Exception is: javax.help.HelpSetException: Could not parse
Got an IOException (http://localhost:8080/app/com.agris.apps.binmgmt.gui.jar!/com/agris/apps/binmgmt/gui/help/!SSL)



OBSERVED APPLICATION IMPACT:
My application is not loading its HelpSet, so help is not available. We will not be migrating to Java SE 6 until this is fixed.

Release Regression From : mustang
The above release value was the last known release where this
bug was known to work. Since then there has been a regression.