Pls heeeeeelpppp..!!!!! Unknown error (1442)

I am using ipod from last 4 yrs. but now i cant use it bcz now it is not playing anything.i dont know what happened to it. when i try to restore it using itune-8 i am getting an error as: the iPod "iPod" could not be restored.An unknown error occurred(1442).
pls help me to use my ipod again.