How to determine if ultrasn0w worked?

Hello,

I am a beginner at this so please bear with me.

iPhone 3G.
IOS 4.1 (8B117).
Baseband 06.15.00.
Carrier Rogers 8.0
Rogers SIM card, no longer active.

I used redsn0w to update the baseband. I then used Cydia to install utrasn0w. Everything seemed to go well. I do not yet have the SIM card of the other carrier I'd like to use. How do I determine if ultrasn0w successfully unlocked my iPhone?

Thanks very much.

If you have a friend who subscribes to a different cel service provider than you, try using their sim card and see if you then have their service on your phone after. If you do then I'd say you're good to go with most any provider

Thanks abica. I procured a French SIM card from a friend and it works.