Hello CarpMan,
Do you have a field called: "Alias" or LogonID" in SQL? If so, it should have the same information located in the sAMAccountName field for users in Active Directory. Verify this by opening the property sheet of a user account in Active Directory and select the "Account" tab. The sAMAccount is located to the right of the "User logon name(pre-Windows 2000):" field. Compare the value of sAMAcccountName with a field used in SQL that contains the logonID. The column used in SQL for logonID or Alias will be mapped to the sAMAccountName in Active Directory when configuring the DTM job.
In the meantime, I will check to see if there is another option that can be used to specify the exact objectClass to return and post the information back.
If you have questions about the information provided above, please let me know. Looking forward to hearing from you soon.