Went through hell to figure this one out… had to also make sure the hostname was not a domain I hosted with google sites.
- http://stackoverflow.com/questions/11696609/php-mail-no-longer-works-after-update-to-osx-mountain-lion
- http://osxdaily.com/2010/09/06/change-your-mac-hostname-via-terminal/
- http://stackoverflow.com/questions/2450589/php-mail-using-sendmail-on-mac-os-x-leopard-10-5-8
- http://stackoverflow.com/questions/11696609/php-mail-no-longer-works-after-update-to-osx-mountain-lion
- http://jspr.tndy.me/php-mail-and-osx-leopard/