I had a use case today where I wanted to move the german strings to german (Germany). There is no way via the UI to do this. I had to hack my zanata.xml file and use hte cli to make this work. I would have likes a means through the UI to make this happen.
What exactly is the desired end result of this? - copy de to de-de, where there would be two locale entries - move de to de-de, so that there is only one entry - or have de to effectively "point" to de-de, that is, "my project's de is de-de" (which would allow the use of client to specify de, and Zanata recognises this as de-de for said project)
Reassigned to PM
Migrated; check JIRA for bug status: http://zanata.atlassian.net/browse/ZNTA-447