IPhone 4 battery was good for a month and suddenly goes dead within 6 hours

Question

I have been running my iPhone 4 (iOS 4.1) for a month without any problem.
Suddenly, two days ago (although I haven't changed anything) the battery goes dead in less than 6 hours...
When I touch the phone, I notice it's warm. I have checked if any app was abusing of the multitasking (by killing all running app in the multitask bar) or the location services (you can tell by the little compas icon next to the battery icon), but it didn't change anything.
I think the last thing I have done, is to purchase my first Multitask application called Avertino. I have since deinstalled it (since I believed it was the root cause of my issue), but no result.
None of my other apps are abusing of the Push Notifications. I am using Push Emails with my Exchange Server, but this hasn't change in years... So this can't be the issue...
Anyways... Something is running and draining my battery, but I don't know what... Reset and Restore hasn't help, but maybe you could?

Answer 1

Speharpre, I wanted to let you know I've figured out what was causing my battery problems, and it may be affecting you, too. I checked wifi, 3G and background apps, but none of these were causing the issue.
In the end, it's my Exchange accounts Push email that was draining the battery so quickly. With Push turned on, the battery drained between 10 and 12% per hour, but as soon as I switched the Push function off, the battery drain went down to about 1%.
All day I've been turning push on for an hour, then off for an hour, the back on for an hour, etc... and each time I switch it back on, I see exactly the same rapid drop in battery.
Still haven't figured out how to fix the problem. I'm going to try deleting the account from the phone and re-adding it, and will also call our server tech support to see if it could be an issue at their end. Either way, I'll let you know.