New Opera 4.1 Beta: How to installed the signed version & get rid of all the network & data prompts in Opera Mini
To download Opera Mini 4.1 beta, visit mini.opera.com/beta using your phone’s existing web browser. This will install the signed version. Please try the one of the versions with certificate (preferably the one with multiple ones).
Now go to Phone Menu->Tools->App. mgr. Select Opera Mini 4.1 and click it. Select Suite settings and set the following settings
[Thx to swankyleo for the tip]