The "locked" status is rather confusing.
The
IEDR made some changes regarding domain status last year in order to avoid issues with registrants jumping around too much and domains getting paid for by the wrong people (or not at all)
Once a domain is registered it will be locked until the reseller (registrar) has paid for it. The domain cannot be moved to another IE reseller until the initial payment has been made.
There's more info on the
IEDR site...