How to find out if my mobile data is working or defective? I installed CyanogenMod 7.2 stable on my Samsung Galaxy Ace before, but it seems mobile data wasn't working. I decided to download the latest nightly build (2013-03-01) but still the mobile data doesn't work.

What are some ways to troubleshoot/test if my mobile data is working? Note: it was working before on stock ROM.
I found the problem: Roaming was active. That's why mobile data wasn't working.

Simply disabling roaming fixed the issue.