I had been using Mobilink Blackberry services for last two years and paying to Mobilink for the BIS (Blackberry Internet Services) for just push email since the blockage of Facebook by the Lahore High Court due to blasphemous page on Facebook. So, I decided to unsubscribe from the blackberry services to save some money 
and activated GPRS. I am now using GPRS/Edge on my Blackberry Curve and enjoying all the services
Mobilink GPRS Settings for Your BlackBerry
Goto Setup -> Advanced Options -> TCP
Add the following details
APN: connect.mobilinkworld.com
User: mobilink
Password: mobilink
restart your blackberry mobile and enjoy the browsing services. I experienced the following applications run smoothly: Gmail, Google Sync, Google Latutude, Web Browsing. Facebook and GTalk simply don’t work on my blackberry curve.
Are you paying for BIS (blackberry internet services) to Mobilink and getting just push email and blackberry messenger? If yes, you should immediately turn off the blackberry services and shift to GPRS or Edge data services offered by Mobilink.
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