Hi & welcome to BBF.

You have 2 choices, 1. enter the vodaphone APN settings at options > advanced options > TCP

2. Go to mini.opera.com from your Blackberry and download it from there , the latest version works over BIS (Blackberry Internet Service) so ne need to enter the APN settings.

Opera Mini works with BIS | BerryReview.com »

Opera cannot be set as the default browser though.