[Solved]: Emails not send out to the same domain

[mrmknet]

I am enabling notifying admin at new comments and new registrations,
emails are sent out of the gallery with no problems to any email address except address@mydomain, I am using sendmail,
when i set admin email address to a gmail address, emails are send, when reverting back to address@mydomain, mails are not sent
This is not a problem with my mail filters because I am using google apps, so my domain mx records point to gmail servers.

[mrmknet]

UPDATE: revealed to be a fault in the DNS configuration, everything is ok now. Sorry, and thanks for everyone