Does a jailbreak use 3G data when not in use?

My iPhone is Jailbroken on iOS 6.1 and I usually leave 3G data on all the time but with the new jailbreak I think it uses more data when I'm not even using my phone. I do not have an unlimited data plan so I need to watch how much data I use. Did anyone else have a problem like this too or is that normal?

A jailbreak should never use your data connection. Ever. At least without asking first. Normally, it's just a tweak or a theme you may have downloaded. Possibly it's getting the latest weather for example?

Anyway, I'd contact your provider, about this because its not normal! Sorry!