quick 3300 battery charge question

Hello, i just bought a 3300 and was wondering i left if charged over night, and the battery bar stopped moving, however, if i unplug the charger then plug it back in, the bars start moving again..... is this defective? should i get a "battery full" message?

thanks

Most likely it isn't the phone, I think it maybe the charger though.

well the thing is, i used both the charger it came with and the charger that came with my 6255i ..... so yeah.. im still confused, how do i know if the 3300's battery is full?