Author Sort & Kindle

[seagull]

So I transfer my MOBI format files to my Kindle and they are sorted by firstname, lastname instead of lastname, firstname. Immediately after the transfer the Kindle recognises the order as lastname, firstname but it refreshes itself to firstname, lastname. Author sort as author is checked and I can't figure out another way to sort them without having the author as lastname, firstname but I really want the author to show up firstname, lastname but sort by lastname, firstname, is there anyway to do this?

EDIT: Figured it out:
Author = Lastname, firstname
Author sort = Firstname, lastname