push notification is not working on iphone4

I have used push notification in my app it works well on iphone3 :) but when I am using iphone4 my app is not ab开发者_Python百科le to get device token . and

- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)devToken 

is not called how can I fix this issue

Push notification wont work in jailbroken device.

I have a jailbroken device and the push notification works fine, so to be exact the push notification service doesn't work on what is called hacktivated devices which are jailbroken devices with no factory unlock.