'Test that adding an IAliasableDomain to a mail service properly sets
up alias group references and such.'

def testAddAliasableDomain(self):

    aliases = object()
    domain = StubAliasableDomain()
    self.S.aliases = aliases
    self.S.addDomain('example.com', domain)
    self.assertIdentical(domain.aliasGroup, aliases)
