I'm new to Zimbra so take what I saw with a grain of salt.
Is this a self-contained single server? If so, I have no clue what would cause that but if not, I would imagine that when you brought up the test server and issued the name change, it contacted the same LDAP (?) server production uses. Just a blind guess though.
But regardless, I would reverse the name change on the virtual test server to the way it was, shut it down and see if the production server is corrected.
LHammonds