After upgrading my laptop to Ubuntu 9.10 Karmic Koala, I found that it did not work properly with the new version of Gnome 2.8 running by default in Karmic. There were buttons that would not click, etc.
This blog provided an excellent solution to the problem:
http://www.economyofeffort.com/2009/10/upgrade-to-karmic-eclipseaptana-u…