Email Addresses and the GAL

[Marauder328]

We have Zimbra integrated into active directory. Our active directory user accounts and email addresses are not the same so we have accounts in Zimbra as ADUser@ADDomain and and alias EmailUser@EmailDomain. We do not want the ADUser@ADDomain advertised as a valid email address either through the email itself or in the GAL as ADDomain is not a valid domain outside of the LAN.

Is there anyway to do this. We set the Cannonical Name such that we use the EmailUser@EmailDomain as the From address but we keep seeing emails that are addressed to ADUser@ADDomain.

Thanks in advance.

~Todd