I'm having an issue as well getting my email to push. I have two Yahoo accounts, a Corporate Sync account, and my Gmail account. Gmail seems to push emails just fine. I do not get any of my messages from the other 3 accounts though. If I open each one and click menu --> Refresh then I get all my unread emails. For some reason though it will not push them to the phone.
My settings are: Data Push is checked, Fetch schedule is set at Every 15 minutes, and Sync over Wi-Fi only is UNchecked on all three accounts.
Anyone have any ideas??