Distributed Session Check

Does anyone know of a way to detect if a session has been created as part of a distributed call. i.e. If the session is being used by a procedure across a database link rather than a direct connection from SQL*plus etc.

Any help would be appreciated,

Regards,
Brendan.

http://download-west.oracle.com/docs..._xa.htm#619981

v$global_transaction

Is there any way of relating v$global_transaction data to a session or v$transaction? From what I can see of the information you can only relate it to v$global_transaction in the remote database.

Thanks for your help,
Brendan