Well many of you may realize that you don't get any push messages in IM or other applications even though you have OS 3.0 and push supported apps running. The problem occurs in hacktivated phones, translation, you bought your phone with contract, depending on one operator's sim card and you activated the phone via jailbreak not from itunes.
Solution is simple, use your legit sim card (at&t, 02, vodafone etc) to activate your phone and then ultrasn0w it and use your other sim card. You can use any of your friends legit sim card as well. Just activate the phone with a legit sim card then do your stuff. Works like a charm