The changes that need to be made are:
- Configure the user attribute targetaddress to contain the remote routing address for the mailbox. This should be in the format firstname.lastname@example.org.
- Set the msExchRemoteRecipientType attribute for the user account to equal 4.
- Set the msExchRecipientDisplayType attribute for the user account to equal-2147483642. (yes, this is a negative value)
- Set the msExchRecipientTypeDetails attribute for the user account to equal to 2147483648