In the 4.5 announcement it claims:
"Zimbra also offers Zimbra Mobile, which provides over-the-air "push" synchronization to mobile devices without the need for third party software or additional servers for most devices."
I'm running the eval, and I setup my Treo 650. It gets my contacts,
calendar data, and email. Nice. But it does it every 15 minutes
according to the schedule I had to set on the Treo. How exactly is
this "push"? I can't see how push is possible, actually. Can someone please
explain this bit of marketing?