win2k/sql2k to win2k3/sql2k5 dtc problems

We're having problems running triggers from a win2000/sql2000 server to a win2003/sql2005 server and vice versa.

enable network DTC access in add/remove windows components is enabled.

What are the steps necessary to ensure that DTC is communicating properly between these two servers?

Thanks for any help,

panic
.