Google Outbound Services Configuration Guide - Manual (Page 89)

94 Outbound Services Configuration Guide
5. On the Network tab, uncheck “Use domain ” and “Enable domain .”
6. In the same tab, check “Route mail through the following smart hosts.”
7. Choose the Add button and enter the name of the smart host. The appropriate
smarthost is
outbounds[your system number].obsmtp.com
where [your system number] is your system number. To find what system to
use, see “Identify Your System” on page 13.