I'm using the XML export in Jira. One of the fields I'm looking at is a custom field of type "user" (I don't know the exact data type, but it's a field that will store the user ID of anyone in Jira). In the XML export, this shows as their username. I'd like it to be the "display name", just like the Assignee field.
Is there an extra parameter I can pass to force resolution? Or some other webservice-like call that I can make to get a user's name from their username?