Abstract: Methods and systems are presented for changing the association of a mailbox from a first domain to a second domain in a messaging system that includes mailboxes organized into domains. Advantageously, the change is effected with only minor interruption to messaging services to the subscriber of the mailbox. With respect to a mailbox record including fields for mailbox name and for a list of other names, the new mailbox name is added to the list of other names and new corresponding names are added also to the list of other names. A change is made to the domain in the record for the mailbox in the table of incoming trunk configuration. After the change in the table, the new mailbox name and the new corresponding names are removed from the list of other names in the mailbox record. The old mailbox name is changed to the new mailbox name in the mailbox name field of the mailbox record. The old mailbox name is added to the list of other names.