[Nobody]

for example, when i open macnn.com on safari, and then when i type the password box using the numpad keys, the keys dont put any single keys i have pressed, and the safari just freezed. this applies to any apps such as textedit, etc. so i have to force quit the apps to make osx works again.
the meaning of freeze is osx's dock doesnt work, the finder doesnt work, the only way just to press cmd-option-escape to force quit the current active application.
its weird. i have tried restarting osx but no luck either.
any help appreciated. thanks..