Syncing gmail -- I want what's on my computer, not what's on the gmail site

I have a gmail account and download my gmail to my mac, and automatically delete messages off the gmail server. I want MobileMe to sync the mailboxes from Mail on my computer, not from the gmail site. When I delete the gmail account from my iPhone, I get only me.com mail from MobileMe, not gmail.

Is there any way to set up MobileMe to get mail from the Mail app on the computer?

Is the only solution to this to leave messages on the gmail server?