Lock screen problem

Hi, I have SUSE 9.2 installed with KDE as desktop environment. When I lock the desktop using Lock screen, I can't get it back. Unlok screen dialog does not accept my password. There is no way to get this locked session back. (Need to reboot system) However I can use start new session option on the dialog and login with same user/password combination. But this creates completely new session and after logout again shows me previously locked session. This is weired... Is this a known bug in SUSE. I am 100% sure that I have not misconfigured any settings. Can anybody help me regain my session? Thanks, -Kshitij