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)

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

A DESCRIPTION OF THE PROBLEM :
A disposed JFrame is still referenced:

private static java.awt.GraphicsEnvironment java.awt.GraphicsEnvironment.localEnv->
sun.awt.Win32GraphicsEnvironment@dfb9b2->
[Ljava.awt.GraphicsDevice;@1273386->
sun.java2d.d3d.D3DGraphicsDevice@a6243->
sun.java2d.d3d.D3DContext@6613e8->
sun.java2d.d3d.D3DSurfaceData@13a15f->
sun.awt.windows.WFramePeer@1766806->
javax.swing.JFrame@106fc94


Note 1: After this JFrame, another dummy JFrame was displayed, and the mouse was moved over it (to work around other Swing leaks, that like to refer the last visible frame).

Note 2: It worked in Java 1.6.0_07

Note 3: It works in Java 1.6.0_12 when setting this system property -Dsun.java2d.d3d=false

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The disposed JFrame should be garbage collected.
ACTUAL -
The disposed JFrame is still referenced

REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER SUBMITTED WORKAROUND :
Disable direct 3d by setting this system property:
  -Dsun.java2d.d3d=false

Release Regression From : 6u10
The above release value was the last known release where this
bug was not reproducible. Since then there has been a regression.