FULL PRODUCT VERSION :
java version "1.7.0_03"
OpenJDK Runtime Environment (IcedTea7 2.1.1pre) (7~u3-2.1.1~pre1-2)
OpenJDK 64-Bit Server VM (build 22.0-b10, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Linux jh 3.2.0-2-amd64 #1 SMP Sat May 12 23:08:28 UTC 2012 x86_64 GNU/Linux

EXTRA RELEVANT SYSTEM CONFIGURATION :
kwin (KDE 4.7.4)

A DESCRIPTION OF THE PROBLEM :
I'm hitting bug 7027598 with Java7. That bug is closed even though there are plenty of comments, reproduceable test cases and even a suggestion about fixing the bug.

It seems someone mistakenly closed the bug as "not a defect" and it's not on anyone's radar anymore. So this is my try to make it visible again.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
See bug 7027598.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The exception should not occur.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
sun.awt.X11.XException: Cannot write XdndAware property
at sun.awt.X11.XDnDDropTargetProtocol.registerDropTarget(XDnDDropTargetProtocol.java:97)
at sun.awt.X11.XDropTargetRegistry.registerDropSite(XDropTargetRegistry.java:571)
at sun.awt.X11.XWindowPeer.addDropTarget(XWindowPeer.java:1914)
at sun.awt.X11.XComponentPeer.addDropTarget(XComponentPeer.java:1374)
at java.awt.dnd.DropTarget.addNotify(DropTarget.java:509)
at java.awt.Component.addNotify(Component.java:6913)
at java.awt.Container.addNotify(Container.java:2758)
at javax.swing.JComponent.addNotify(JComponent.java:4734)
at java.awt.Container.addNotify(Container.java:2769)
at javax.swing.JComponent.addNotify(JComponent.java:4734)
at de.gebit.trend.gui.GBasicPanel.addNotify(GBasicPanel.java:612)
at java.awt.Container.addNotify(Container.java:2769)
at javax.swing.JComponent.addNotify(JComponent.java:4734)
at java.awt.Container.addNotify(Container.java:2769)
at javax.swing.JComponent.addNotify(JComponent.java:4734)
at de.gebit.trend.gui.GBasicPanel.addNotify(GBasicPanel.java:612)
at java.awt.Container.addNotify(Container.java:2769)
at javax.swing.JComponent.addNotify(JComponent.java:4734)
at java.awt.Container.addNotify(Container.java:2769)
at javax.swing.JComponent.addNotify(JComponent.java:4734)
at java.awt.Container.addNotify(Container.java:2769)
at javax.swing.JComponent.addNotify(JComponent.java:4734)
at java.awt.Container.addNotify(Container.java:2769)
at javax.swing.JComponent.addNotify(JComponent.java:4734)
at de.gebit.trend.gui.GBasicPanel.addNotify(GBasicPanel.java:612)
at java.awt.Container.addImpl(Container.java:1114)
at java.awt.Container.add(Container.java:966)

REPRODUCIBILITY :
This bug can be reproduced always.

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See bug 7027598.
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