Can't create computer account in Workgroup Manager

Question

Hi everybody !.
I am installing a new Xserve with Mac OS X Server 10.5.6 and I am having some trouble with computer accounts in Workgroup Manager.
I have a couple of PCs with Windows XP that I have added to the Windows domain created by Mac OS X Server with no problem,and they do appear in my computer account list, with the name PC_NameX$.
My Xserve also appears in this list with the name ServerName.DomainName$
But my iMacs (with Mac OS X 10.4.11) are not listed. When I try to create their accounts, I write their names and their MAC address but when I push the button "Save", Workgroup Manager says that I can't create this account because there is a computer with that name and that MAC address yet.
I can't find a solution for this problem by myself. Could anybody give some advices to solve it ?.
Many thanks.

Answer 1

Hi Mabel,
In my computer list appears my Windows computer names (followed by a "$" symbol, i.e., name$) and my Xserve name followed by domain name and a "$" symbol, i.e, name.domain$. Finally, there is a Guest account I added a few days ago (without "$" symbol).
No iMac is listed here. When I try to add them manually, I write "Name", "Short Name" and "Ethernet ID" fields, and when I push "Save" button, I get this message:
"The name you have chosen conflicts with a name assigned to another computer. You can’t assign the name “Pollux” to two different computers. Remember that names are not case-sensitive when checking for conflicts." (Pollux is the name I gave to one of the iMacs).
If I change this name and use another one, but I don't change "Ethernet ID" and then push "Save", the message is:
"The ethernet address you have chosen conflicts with an ethernet address assigned to another computer. You can’t assign the ethernet address “00:17:f2:d3:38:95” to two different computers."
So, It seems that WGM knows Name and Ethernet ID from this iMac because it does not let me type them again, but I have not typed this information before nor the iMacs are listed in computer list.
This is what I don't understand.
I have have read chapter 6 "Setting Up Computers and Computer Groups", the one that starts on page 105, from top to bottom. I have not found a single clue that helps me solving this problem. Here explains the procedure when everything is working properly.
Finally, another piece from the puzzle. There is an iMac, that always connects to Directory with Airport interface. I have tried to add this iMac, manually. Well, I get the name conflict message, the Ethernet ID conflict message (with its airport id) and... an Ethernet ID message when I type its Ethernet ID. It seems Directory knows this Ethernet ID even, it has never been used to connect to it.
Is there some detail I am missing ???.
Kind regards.