I have an iPhone 3G on 4.2.1 jb and unlocked. I do NOT have a data plan (I'm on tmobile). So when I lock my screen the wifi symbol disappears so I don't get in push... The only fix I found was fetching mail every 15 min and then I'd receive the notification every 15 min. When I wake my iPhone up, it takes around 5 sec to connect back and THEN the notification will pop up. Im not sure if pushfix will fix my problem because I used a AT&T sim card to get past the lockscreen in the beginning (but the status bar said no service) sooo can someone please help me???