Version:            (using KDE 4.2.2)
OS:                Linux
Installed from:    SuSE RPMs

Keyboard occasionally stop working. I cannot detect any pattern why it happens. Sometimes I cannot see this problem for several days, on other days it might freeze several times.

When keyboard is lost, I cannot enter anything to any application. I believe NumLock and CapsLock LEDs stop reacting as well. 

Keyboard restored when I logout using mouse. Then I can type my password and login again. 

Most often it happens while I use AlbumShaper while editing photoalbums. Usually after a while I notice that keyboard is gone and I cannot type anything. Quite often it happens while I type text in FireFox. But I think there is no connection to any particular application, it might disappear at any time.