Set up th email client (mail or outlook express) on your computer to check your gmail account. You have to have pop enabled in gmail for this to work. There is also link in there that gives you the smtp and pop3 setting for you mail client.But how in the world can we do that on the iPhone with a Gmail account?
Make a filter in your mail client to skip/delete/archive/whatever all mail where from is = to me.
When your iPhone sync's with the mail client it will move the filters to the iPhone as part of the sync.
All 3 email accounts I check with Mail (mac) client, transfered over to my iPhone on the first sync. I did not have to set up any of my email account in the iPhone. They all moved over from the client.
Including my gmail. For gmail you build the filter in the web interface.
Ohiostateboy and I worked on this most of the night and this is the solution we are using.