Does AT&T allow jailbreaking?

I want to know if AT&T will care if my iPhone is jailbroken or not. Will they do anything if they find out it is? I have not unlocked the device or anything that affects the cellular use of it; I have only installed themes, and other customization tools. If anyone could tell me if they would care, I'd appreciate it.

Jailbreaking is not illegal and they won't care if you do but if you have a warrenty i would not suggest doing it cause it will void your warrenty

Well no, of course not. Its not illegal but they wouldn't want it jailbroken. You void Apple's warranty doing it though.

I think the cops are more upset if you break out of jail.

AT&T doesn't care but it will void your warranty on all phones you do it too.