My laptop is ThinkPad R52 running Ubuntu Jaunty. The Skype has been installed from medibuntu repository, 2.0.0.72-0medibuntu4. It was really bad to use Skype. CPU utlization was always 100% during call. The problem should be kernel or alsa driver due to mishandling input/output buffer to sound card. The pain is over today after I found solution.