Well After i updates from kubuntu 8.04 to kubuntu 8.10 i had many problems such as :
The KDM not autoatically starting !
After making some searchs on this forum i found a way to fix it by sysv-rc-conf
But now i have a new problem : mouse and keyboard not working on kdm so i login from tty1 and restart it , and everything gets fine

Can you please help me To solve this problem ?