FULL PRODUCT VERSION :
java version "1.6.0_12-ea"
Java(TM) SE Runtime Environment (build 1.6.0_12-ea-b02)
Java HotSpot(TM) Client VM (build 11.2-b01, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

EXTRA RELEVANT SYSTEM CONFIGURATION :
I can't see that there's very much else that's relevant.

A DESCRIPTION OF THE PROBLEM :
Since about Update 12, the Java plugin stops working about 80% of the time after I resume my laptop.  The Java icon disappears from the taskbar, and attempts to access Java from within Firefox extensions fail.

This is not unique to my machine; other users of my Firefox extension have seen the same problems.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Get a laptop.
Install a Firefox extension which uses Java (e.g. http://wiki.modplugin.org, though there are probably simpler ones).
Go to a Yahoo group with Freecycle in the name and check that the extension does stuff on screen.
Suspend and resume the laptop.
Reload a Yahoo groups page.


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Extension does stuff on screen as before.
ACTUAL -
You'll see an error popup about Java not working.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
There's no Java specific error that I can provide - the Java console disappears.

REPRODUCIBILITY :
This bug can be reproduced often.

CUSTOMER SUBMITTED WORKAROUND :
Restart Firefox.