howto disable gtk look of swing apps?

This is an "at your own risk" type of issue. It has been reported as a "Wishlist Bug" item ( https://bugs.launchpad.net/ubuntu/+source/openjdk-6/+bug/183139 ) and developers know about it. However, I am only pointing you in the risk directly.

Depending on the version of Ubuntu you are running this may help you or you may benefit from it if you are a developer-type:
http://ubuntuforums.org/showthread.php?t=241868
Also: http://technolark.blogspot.com/2008/11/swing-applications-freezing-in-ubuntu.html

I wish I could offer more guidance, however I understand your frustration.

Craig

# ls -l /usr/lib/jvm/java-6-openjdk/jre/lib/swing.properties
lrwxrwxrwx 1 root root 36 2009-03-14 23:39 /usr/lib/jvm/java-6-openjdk/jre/lib/swing.properties -> /etc/java-6-openjdk/swing.properties

# cat /etc/java-6-openjdk/swing.properties
swing.defaultlaf=javax.swing.plaf.metal

$ java -version
java version "1.6.0_0"
IcedTea6 1.3.1 (6b12-0ubuntu6.1) Runtime Environment (build 1.6.0_0-b12)
OpenJDK Client VM (build 1.6.0_0-b12, mixed mode, sharing)

but i still see gtk look of swing apps. Craig, thanks for your reply, but i just want enable metal-laf, instead of that crappy gtk-laf (https://bugs.launchpad.net/ubuntu/+source/openjdk-6/+bug/183139 here peoples wanna GTK instead of metal by default), what is the "risk" you wrote about? i don't use GIJ and any patches for "Mac-style shit".