Problem I had when upgrading from Ubuntu Jaunty 9.04 to the Karmic 9.10 beta:
Eclipse (and Aptana) exhibited a number of UI issues. Buttons clicked would perform no action. The update/install new software window would be blank where it was supposed to show the options of software to install (you could click where the options should be and see their text description appear below, but you could not see what you were clicking on).
The solution, at least for now, is to create a script like this:
Remember to “chmod +x” that script to make it executable. Setting the GDK_NATIVE_WINDOWS environmental variable to True will fix those UI issues, at least while we wait for newer Eclipse/Aptana builds that work better with GTK+ 2.8.