Low Battery Backup In Nokia 2690 problem

I have purchased Nokia 2690 1 month back. The handset is really nice and has some excellent features. But from last few days i am disturbed by it's very low battery back up. The battery doesn't survives for even a day, even though i am not a frequent talker on phone. The phone battery tends to die in 4-5 hours. I have visited customer care of Nokia, they had installed a software and has asked to scan my memory card for any viruses in it . I got my my memory card scanned. But the problem stands there as it was....

If anyone of you could help me out with a solution i would be glad.