There are some "Group Policy" settings for winXP that are can be edited by entering "gpedit.msc" at the run menu.
In my case, the one I wanted changed was:

> Administrative Templates > Windows Components > Terminal Services. Enable > Limit Number of Connections

This data is not stored in the registery, instead it is stored in \Documents and Settings\All Users\ntuser.pol
Fortunatly this file is not created until after gpedit.msc is run the first time. So in order to make changed, one simply takes the ntuser.pol file from a computer that is already setup as the user likes, and adds it to their unattended windows install CD in the following location:

:\$OEM$\$1\Documents and Settings\All Users\ntuser.pol

I have only tested this on XP Pro SP2, but it works perfect in my install.

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