If ya, turn the battery and check out the 26 digit code
enter this 26 digit code here
If your battery is one among the defected ones , Nokia is replacing them free of cost as 46 million batteries manufactured by Matsushita between december 2005 and November 2006 has been reported to have caused battery expansion due to heating.
I jus' checked out mine and the other Nokia phone at home , both the batteries seem to be fine and does not fall under this category . Check your batteries too and be safe .