Mail passes ORF but never hits Exch Tracking - ORF Forums

@Craig Reilly: If ORF logged the email was whitelisted, that means it actually did nothing to it (other than monitoring the SMTP transport). Note that ORF has no control over the actual delivery of emails: it is entirely up to Exchange, ORF cannot force the email delivery upon its whitelisting (it can only tell Exchange to reject the email if the email fails on a blacklist test).

I recommend checking the SMTP transport logs if you have that enabled: http://technet.microsoft.com/en-us/library/bb124531.aspx

Also, if you have any other software installed through the emails are relayed, check the logs of those as well, plus the queues and the Junk folder of the recipient.