Dieser Beitrag wird recht technisch, und damit davon möglichst viele was haben, geht’s auf Englisch weiter 
Recently, I experienced some problems debugging an Java/Swing application on my Ubuntu Linux box using IntelliJ IDEA 10.5 . The problem is that java.awt grabs control of all input devices while running. If you place an breakpoint inside an swing method (e.g. related to drag&drop behavior), the debugger will stop there but you will not be able to continue due the lack of a way to send commands to your IDE/debugger – java.awt has blocked all input devices.
With Linux, fortunately, you can always hit Ctrl+F1 to switch to a console and use jps (as a nice alternative to ps -axf | grep java; but it can do much more – see the linked man-page ) to get the ID of the debugged thread and kill it (kill -9 ProcessID)
After some research i found the BugReport in Ubuntu Launch Pad which redirects to Orcale’s bug tracker: IDE (…) Debugger hangs process on Linux, which suggests the -Dsun.awt.disablegrab=true JVM parameter as a solution work-around.
Unfortunately, this doesn’t work for me – the UI gets still blocked.
At least, IDEA is capable of breakpoints writing messages to console (even evaluated ones; see configuring breakpoints), so I still don’t need to clutter the source-code with System.out.println() …
Another nice thing i learned while trying to hunt this problem down, is the tool jstack which can be used to get an stack trace from any Java process at any time 
So, up to now, I haven’t solved the problem but leanred once again some more bits and pieces of the javaversum. There is also a thread on this at the jetbrains forum.
If someone has any suggestions: You are more than welcome