FULL PRODUCT VERSION :
java version "1.6.0_17"
Java(TM) SE Runtime Environment (build 1.6.0_17-b04)
Java HotSpot(TM) Client VM (build 14.3-b01, mixed mode, sharing)
ADDITIONAL OS VERSION INFORMATION :
Linux 2.6.31-17-generic #54-Ubuntu SMP Thu Dec 10 16:20:31 UTC 2009 i686 GNU/Linux
A DESCRIPTION OF THE PROBLEM :
See Bug 6714678, which is still broken.
Since I cannot reopen it, I'm filing this bug instead.
STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Set a breakpoint somewhere in a method triggered by an event/action handler (e.g. a button press).
Once the application hits the breakpoint, the X window system freezes. Workaround as in issue 6714678.
EXPECTED VERSUS ACTUAL BEHAVIOR :
Freeze. The only way to unfreeze is to switch to a console and kill the debugged java process from there.
This bug can be reproduced always.