I'm running SBS 2000 and XP Pro on desktops, Outlook 2003 and 2002. I read Microsoft's
http://support.microsoft.com/?kbid=327000 and did as directed. However, the emails going out still have "delegate on behalf of acc. owner". So, I setup "send as" permissions and checked to see if "send on behalf" was on -- it wasn't. The Outlook delegate is set to default email box as Exchange Server. I don't know what else to check.
http://support.microsoft.com/?kbid=327000