What happened to an inbound or outbound message? Was a message sent to my domain and marked as spam? Which users sent or received a specific message? Starting today, domain admins can get answers to these and other such questions using Gmail log search. This feature is now available in the administrator control panel.

Languages included:
US English only (Next Generation release only)

For more information:
http://support.google.com/a/bin/answer.py?hl=en&answer=2604578
http://googleenterprise.blogspot.com/2012/07/gmail-log-search-feature-enhances.html