I'm guessing by the title of the thread you need to connect to iTunes. Jailbrakers always seem to have problems with receiving push notifications. As far as I'm concerned you can't beat not being jailbroken. It kind of takes away from the 'It just works' philosophy of Apple when all you get is problems. But if I was you I would have a look on the more jailbreak specific websites or restore and rejailbreak if you can't find a fix.
I posted this on another thread. It seems to have worked for me at least, I went into settings>notifications and for everything I had in notification centre, I turned off 'view in lock screen', exited settings and then went back in and turned them back on. Since then I've been getting a few notifications which I wasn't getting before, mostly facebook but also mail. I don't think I've been missing any since I did this but it may be a bit early to say.