Nokia 6600 Help required please!!!

Hi Guys n Gals
I have nokia 6600 on orange and I have recently tried to unlock the phone using codes calculator from the internet. Everything went fine and I even got the message on the phone "sim restriction off" meaning the phone is unlocked. Now when I am inserting any non-orange sim the phone starts off and after few seconds it shuts itself off. It only happens when non-orange sim card is inserted. With orange sim there is no problem what so ever. What could be the problem?

Cheers in advance

Max

[shoehorn]

There's a load of info and support on the 6600 here...
It's definately worth a look anyway....