I find the "comma after full name" version the best and easiest way to sort FIRST, LAST...
but someone over at XDA forumn posted some .cab files that "...give you an option in the pop-up menu when you tap and hold a contact on how to show the contacts. "
You can get the files
HERE, 3rd post down. There's 4 different ones.
*Note, you have to register first at XDA forums before you can see the .cabs to download.