I've got the following situation, and it's driving me crazy:
One VPS, with
domain2.com websites hosted.
domain1.com I use the VPS mail functionality and for
domain2.com I use Google Apps (and GOogle Mail).
When I send an email from firstname.lastname@example.org it will arrive correctly at email@example.com, but when I send an email from firstname.lastname@example.org it does not arrive at email@example.com... I get a Mail delivery failed: returning message to sender at my sending inbox.
The sollution looks quite simple to me (dns?) but I can't find it. VPS running CentOS 5.0 and DirectAdmin 1.40.3 (i've asked this on stackoverflow but no response :) )