We have an existing Data Center JIRA instance with usernames based on the first five letters of the user's last name and the first two letters of the user's first name (5 + 2), "lastnfi" for example. We are planning to move to the JIRA instance hosted by another organization with user accounts attached to a certificate and based on the user's first name and last name, "firstname.lastname.ctr" for example. We are looking for a way to associate all of our existing JIRA issues in our existing instance, which are based on a user's 5 + 2 name, with the corresponding certificate based accounts in our destination instance. Is it possible to map the two types of accounts, given that we would be able to supply the translation in either a database table or XML configuration file?