Use the new At&t sim card in a Cingular phone?

[Beau B]

Yes, it should work with no problems at all.

 

[ShopGirl]

Hello,

I am trying to find a good replacement phone for use with an At&t sim card. This is the new At&t merged with cingular.

I want to know if the At&t sim will work in an treo 650 cingular phone...