FULL PRODUCT VERSION :
Java(TM) SE Runtime Environment (build 1.6.0-beta2-b76)
Java HotSpot(TM) Client VM (build 1.6.0-beta2-b76, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Linux linux 2.6.13-15.8-smp #1 SMP Tue Feb 7 11:07:24 UTC 2006 i686 i686 i386 GNU/Linux, Suse10.0

A DESCRIPTION OF THE PROBLEM :
The system property documented at http://java.sun.com/javase/6/docs/guide/2d/flags.html#aaFonts

awt.useSystemAAFontSettings=on,off,lcd.... and marked as fixed in bugs number 6291810 and 6322391, which should enable or disable various AA rendering hints on systems where Java cannot pick up System properties, like KDE, Win 2000 etc. doesn't work when set from command line

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Try opening any Swing program under KDE with -Dawt.useSystemAAFontSettings=on(lcd,gasp...), fonts should be using plain or lcd AA, but they aren't. I can even reproduce it on Gnome, when Gnome AA settings are off, and I try to force Swing to use AA.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Judging from Suns own documentation, -Dawt.useSystemAAFontSettings=on should give AA fonts in Swing applications, regardless off system settings
ACTUAL -
Fonts stay nonAA

REPRODUCIBILITY :
This bug can be reproduced always.