A descriptive name for the group. If this group connects to
a single remote MTA this should be the name of that MTA. If
this in turn is an Internet MTA this should be the domain
name. For an OSI MTA it should be the string encoded
distinguished name of the managed object using the format
defined in RFC 2253. For X.400(1984) MTAs which do not
have a Distinguished Name, the RFC 2156 syntax
'mta in globalid' used in X400-Received: fields can be
used.