Probably not... Because if mojang changed it for one person, then pepole would find out, and want theirs changed, and mojang wouldn't be able to cope with so many user name requests. Its possible that in the future they may write some kind of automated system, where it automatically changes the data in the database, as it would create the data when you created your minecraft account, but I think the chances of mojang doing personal requests like that are very slim. Your best bet is to work out where mojang takes suggestions for things like this and post the idea there.