Login password problem

From yesterday I am facing a problem with my login password. After startup when the system is asking my password , when I am typing my password each number is showed three times in the box. I am explaining more, let my original password is 123. In the box when I am typing 1 , it is showing three ***. Similarly for the others and the total password becomes a 9 letter pass word as *********. Whereas my password is only in three letter. After happening this I have tried to change my password from system setting > Account details. There is also same problem , I mean 3 times for one pressing. But the system is working with that password. The problem is same for KDE wallet.But there is no problem in text typing in any area. Any idea ? how to solve this ? I am using Kubuntu 10.10