Hmmm, some techie you have there !
Yes you can use XP Pro and Home clients on a Windows 2003 Domain
network. However, there are a few differences in the way each type of PC
will behave on the Domain.
XP Pro machines can be configured to be Members of the Domain and hence
login to the Domain on startup. In otherwords, the login ID you use to
login to the PC must be valid on the Domain Server. All access rights to
shares, printers, internet, other PC's etc is controlled via the server
and hence you can forget about it once logged in.
XP Home machines only know about Peer-2-Peer networks where NO Domain
server exists (ie: Home or Small networks). When you log into the
machine you will always log into the local machine and never the Domain.
The difference comes when you want to access network resources
controlled by the Domain (ie: network shares, printers, internet
connection etc). As the PC has not logged into the Domain, the server
requests authentication before allowing you access. In otherwords, it
asks you for a username and password. Once you have supplied this
information once, you can keep re-using the resource until the PC or
Server is rebooted. The only real exception to this is your internet
connection, which will ask for authentication each time it is accessed.
An XP Pro machine will behave just like an XP Home machine if configured
as a Workgroup computer rather than a Domain Member.
An XP Home machine can never become a member of a Domain, crazy but
thats M$ for you.
Your scenario is a very common one for most companies because MOST
laptops are supplied with Home and not Pro. Finding a laptop with Pro
installed is very hard. Normally you have to buy another Pro license.