My iPhone 4's push notifications have stopped coming through. This happened about 2 weeks ago. I've tried turning Notifications Off then On, and I've tried a soft reset of the device, no luck. I downloaded an app that purports to test push notifications, and it reported that all was ok. I have 4.2.1, jailbroken with Greenpois0n, but I don't think this is the issue because they worked fine for weeks after doing the GP jailbreak on 4.2.1. I haven't actually done much at all with my phone in recent weeks, I've mostly being playing with my iPad (which is also jailbroken on 4.2.1, and Notifications work fine). UPDATE: I just remembered, my iPhone 4 was replaced by Apple 2 weeks ago under warranty (faulty home button). Could the new handset be something to do with it?