I use Aptana Studio 3.0 in XUbuntu and I got this problem too.
After I used the Find and Replace function, the key board is not working anymore. I have this problem with Zend Studio 5.5.1 too.
Aptana Studio 3, build: 3.0.8.201201201658
$ dpkg -l | grep libgtk2.0-0
ii libgtk2.0-0 2.24.6-0ubuntu5 The GTK+ graphical user interface library
ii libgtk2.0-0:i386 2.24.6-0ubuntu5 The GTK+ graphical user interface library
$ uname -a
Linux minh-desktop 3.0.0-15-generic #26-Ubuntu SMP Fri Jan 20 17:23:00 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
I use Aptana Studio 3.0 in XUbuntu and I got this problem too.
After I used the Find and Replace function, the key board is not working anymore. I have this problem with Zend Studio 5.5.1 too.
Aptana Studio 3, build: 3.0.8.201201201658
$ dpkg -l | grep libgtk2.0-0
ii libgtk2.0-0 2.24.6-0ubuntu5 The GTK+ graphical user interface library
ii libgtk2.0-0:i386 2.24.6-0ubuntu5 The GTK+ graphical user interface library
$ uname -a
Linux minh-desktop 3.0.0-15-generic #26-Ubuntu SMP Fri Jan 20 17:23:00 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux