Gingerbread on Samsung Galaxy Mini
You could send a mail to Samsung Pakistan, and ask them.

The ROM for the Galaxy Mini (and every Samsung) has specific Samsung components (TouchWiz, Samsung Apps, etc). And comes with a language pack specific for each region. Eventually every provider can add his stuff.

So it is up to the combination Samsung and provider when (or if) a new version of Android is released.

I know of some friends that have been able to upgrade their provider branded phone to Gingerbread, while my non-branded phone does not have the update (yet).