[Testing Environment]
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.2.1) Gecko/20030131
Linux freekick.PRC.Sun.COM 2.4.18-14 #1 Wed Sep 4 13:35:50 EDT 2002 i686 i686
i386 GNU/Linux
Java(TM) Plug-in 1.4.1_02-b06

[Repro Steps and Bug]
1. Run the testcases listed here
http://www.mozilla.org/quality/browser/front-end/testcases/oji/javatojstests.html
2. Among these cases, 5, 9 and 11 will not display any error message;
3. Browser HANG without any error message;

[Addition]
I separate this bug with 4837766 because of there is no error message displayed when browser HANG; I don't think they are one same problem;