No matching DOM Vendor

I am using BCB6 on Win2K with all service packs, but since the BCB SOAP
groups seem to be dead, I though I'd give the Delphi groups a try...

I have a client app that accesses data from a SOAP data module (via
TClientDataSet, MIDAS, etc...).  I am building the app with runtime packages
and dynamic RTL.  Everything works fine, but if I add SOAPRTL to the list of
runtime packages, then I get

No matching DOM Vendor: ""

when attempting to access the remote data module.  If I remove this package,
from the list, all is well.  I have checked (when including the BPL) that
MSXML is indeed the default DOM vendor and is registered.  Any suggestions?