What is the proper way to set up user using external mail servers?

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http://forums.cpanel.net – Most of my domain emails are set up through Gmail's mail servers. On my old server (not a cpanel) I have to comment out the domain names in my local-hosts-names manually to ensure that mail is delivered properly. I've noticed on my cPanel servers that I can comment them out manually, but they keep getting overwritten. What is the proper way to do this? Is there a setting I'm missing when I add a new domain? How can I adjust the ones I've already added to the servers? Virtual cookie for an answer! Noob with boobs, Lena (HowTos)