Allowing application servers to relay off Exchange Server 2007

To allow application servers to relay through your Exchange 2007 server do the following

Create a new internal receive connector in EMC
Add the servers that need to relay
When created edit the settings and navigate to Permission Groups
Select only Anonymous users, deselect other options
Navigate to the Authentication tab
Deselect every checkbox so that nothing is selected
Apply changes
Open EMS and run the following commandlet
Get-ReceiveConnector “InternalRelay” | Add-ADPermission -User “NT AUTHORITY\ANONYMOUS LOGON” -ExtendedRights “ms-Exch-SMTP-Accept-Any-Recipient”
Relay should now work for the selected servers