COM+ Application server has problems with SQL2000 both Win2003

Hi,
I want to run the following scenario:
1 server with COM+ components do DTC transactions against a SQL-2000
database. While this runs perfectly under Windows 2000, this does not work
at all under Windows 2003. I have checked all MSDN stuff, run the DTCTESTER
utilitly and came to the result, that is must be some network problem.
But: I have no idea how to resolve it, both are set to use TCP/IP, no
firewall is active, ping and drive mapping (in both directions) is
successful, also retrieving data via query analyzer is possible. Now which
setting must I change, so these machines can do those DTC transactions?
Regards
Is netbios name resolution working in both directions?
Can you make connections using ISQL.exe both ways without errors?
Did you restrict the rpc ports on the firewall for MSDTC?
Thanks,
Kevin McDonnell
Microsoft Corporation
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