Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0_1 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A306 Safari/6531.22.7)
Settings > General > Reset > Reset all settings (the first one at top won't reset or erase your contents).
Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0_1 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A306 Safari/6531.22.7)
Settings > General > Reset > Reset all settings (the first one at top won't reset or erase your contents).
I'm having the same issue. I have done general reset, holding button reset, reboot and respring. Push works solid for a little while after I do either one of the resets but then becomes very spotty. Yahoo Mailbox, gmail is even worse for me.