OID value: 1.2.840.113533.7
Entrust Technologies security OIDs.
The reason for this being a sub-OID of Nortel Networks' OID is that it was assigned at a time when Entrust was Nortel Secure Networks. Entrust now also has a separate OID tree rooted at 2.16.840.1.114027, but assignments under this tree still belong to Entrust.
See also the OID Repository website reference for 1.2.840.113533.7