Two coditions to enable uma connections on blackberry devices like curve 8900....etc..

1. Need a device equipped with UMA fuction like blackberry curve 8900, but blackberry bold doesn't support UMA connection. Connection preference option does not appear in manage connection option in home screen if the device doesn't support uma. Bold doesn't have this option.

2. If u have a device with uma support, then you need to subscribe to UMA plan to avoid additional charges on voice transmission thr uma connection. Without this plan all voice data transmissions are charged by the service provider, but with uma plan, they are not charged. Internet connection thr wireless option on the any devices are not charged, but thr mobile network, all internet connections are charged.