JDK/JRE tested: JDK 5.0u20 b02
OS/architecture: 32-bit Windows XP.
Reproducible: Always
Reproducible on machine: Any windows box
Also reproducible on machine: xpsc3.ireland.sun.com
Is it a browser specific regression: Y
[If yes] Is it a new browser support: Y
[If yes] Regression relative to browser version: Firefox 3.5 Beta 4 & 5
Is it a Regression: Y (browser to browser regression)
[If yes] Regression introduced in browser release: Firefox 3.5 Beta 4 & 5
[If yes] Tests pass on browser version: Firefox 3.0.11 (latest live firefox)
Test run log location: Attached to this bug.

Steps to reproduce:

1. Download & install Firefox 3.5. Beta 5 from the following location.
http://www.mozilla.com/en-US/firefox/all-beta.html

2. Install 1.5.0_20-b02 jre from the following location.
/java/re/jdk/1.5.0_20/promoted/fcs/b02/bundles/windows-i586/jre-1_5_0_20-windows-i586-p.exe

3. Launch the firefox browser. Make sure the Java Console is display (via Firefox, click Tools -> Java Console).

4. Browse to the following url.
http://sqeweb.sfbay.sun.com/deployment1/mantis_ws_plugin/doc/proc/JPI_JSobject.html

5. Scroll down to "JSObjects tests for Netscape" link. When you click this link the
tests will be run automatically. The 6 tests will take between 3-5 minutes to run automatically.

The following exception was displayed in the console when executed using Firefox 3.5 Beta4/5.

netscape.javascript.JSException
at netscape.javascript.JSObject.getWindow(Unknown Source)
at locmeth_Test.start(locmeth_Test.java:18)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

When the tests are executed against Firefox 3.0.11 using 1.5.0_20-b02 there is no exception and all the tests pass.

NOTE: These tests pass with both Firefox 3.0.11 & Firefox 3.5 Beta 4/5 when run using 6u15-b01 (new-plugin), they fail in 6u15-b01 (classic-plugin mode).

I have attached 3 files which show the tests passing with Firefox 3.0.11 & failing with Firefox 3.5 Beta 4 & 5 (including exception).

I am ticking "Regression" as this is a browser-to-browser regression.