OK, on the Windows 2003 server you need to install the networking part of DTC.
In Add/Remove Programs / Windows Components > Application Server > Enable network DTC access
Reboot if prompted
Open Start > Programs > Admin Tools > Component Services
Under Console Root > Component Services > Computers > My Computer right click on My Computer and select Properties
MS DTC tab
Security Configuration button
Check every check box, select the bottom radio button. Do not change the Windows Account listed.
OK all the way out and DTC will restart.
You should be able to run a distributed transaction between the machines. You can watch the Transaction Status under My Computer > Distributed Transaction Cooridenator.
Denny
MCSA (2003) / MCDBA (SQL 2000)
MCTS (SQL 2005 / Microsoft Windows SharePoint Services 3.0: Configuration / Microsoft Office SharePoint Server 2007: Configuration)
MCITP Database Administrator (SQL 2005) / Database Developer (SQL 2005)
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