FULL PRODUCT VERSION :
java version "1.6.0_12"
Java(TM) SE Runtime Environment (build 1.6.0_12-b04)
Java HotSpot(TM) Client VM (build 11.2-b01, mixed mode, sharing)

Encountered in 1.6.0_7 to 1.6.0_13, may happen in earlier and newer version as well


ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.0.6001]


EXTRA RELEVANT SYSTEM CONFIGURATION :
We did not encounter this Error on WindowsXP, but this may be just coincidence.

A DESCRIPTION OF THE PROBLEM :
The following Error is raised occasionally under Windows Vista in applications with a (Swing) GUI.

Exception in thread "AWT-EventQueue-0" java.lang.StackOverflowError
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
...

The application is in an almost unresponsive state then.
We had this error several times on different machines running Windows Vista without a recognizable relationship to the user activity. Well, it *seems* to happen more often after some inactivity.


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
No safe way to reproduce. Perhaps, run a Swing application more complex than hello world and wait...



ERROR MESSAGES/STACK TRACES THAT OCCUR :
Exception in thread "AWT-EventQueue-0" java.lang.StackOverflowError
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
at sun.awt.image.ImageWatched$WeakLink.isWatcher(ImageWatched.java:84)
...

REPRODUCIBILITY :
This bug can be reproduced occasionally.