I've submitted an mod to Modmyi which should be around on Cydia very shortly
and this will be a very good mod for some.
I done this cause im so annoyed with Apple - I purchased my iPhone think
push create just connect up to my personal IMAP mail server and working -
Only to find only Yahoo! and MobileMe from Apple support it :(
I then looked into a bit and created a Mod which ive submitted to Cydia so
you can turn any mailbox into a push mailbox - GMail, Personal Mail Server
or any other server.
Remember when your iPhone is in standby it will use the Cellular Network
Data so make sure you on an Unlimited Plan other wise you be losing all your
Bandwidth to your mail client.
Also i was amazed on how little battery
was used it only used 2% of
battery every 30
minutes in standby