I need my J2ME app to run in the background and still allow the user to use his mobile without problem. the app still needs to process some events in the background.
If you app is in background then it doesn't receive any events. So I don't know how it can process any event in the background. If its a preload J2ME app then you can work with the handset manufacturer and obtain certain jad attributes to put your midlet in background. You can thus not allow the user to exit the app. You may want to think this use case through.
On the other hand you can do all these in Blackberry apps.