Entourage User Account Diables Itself Every Week or So

Question

Running Mail Service on Apple OS X server package 10.4.4 (problem also was on 10.4.3) we have two customers whose log in account becomes disabled every week or so, as though they had made too many erroneous attempts to log in. We reset their account, and they're good to connect for a few more days, then they contact us to say they can't log in, we check the workgroup manager and, sure enough, the log in permission has disabled itself.
Anyone else seeing this? They are also Mac users, too. They thought they "needed" the features of Entourage. No other email customers using this mail server are complaining at all, although probably no others are using Microsoft Entourage.
We're pretty suspicious this is an issue between Microsoft Entourage and the Open Directory. Occasionally we see one of these users logged in twice at the same time on the server connected users monitor screen.

Answer 1

Here is the error I get, if it helps.