It seems there is a problem with the Java IDE NetBeans 5.5 when it is running under XFCE. If you click something in the Menubar, the Menues are jumping around and there always opens another menue than you have clicked. For example, you click on "Edit", but Menu "File" opens. So the program is not usable because you can't activate the Function you like.
It seems, that the problem is somehow concerned with maximized windows, when you resize the windows manually and wait for a minute or so, the program reacts normally.
I have the confirmation of at least another user with the same problem, and he reports, that the problems are non-existant, when the IDE is running under GNOME.
Created attachment 1024
Fix ICCCM configureNotify
The problem comes from an interpretation of ICCCM standard. The attached patch fix the issue.
This is not a major issue nor a high priority. This does not affect the system stability, you do not loose data, nor it's a security issue that would require a urgent fix.
This is now fixed in SVN trunk, branches/xfce_4_2 and branches/xfce_4_4