my fault flyers2114 missed that in your post.
also, maybe what you are trying but are u using the 'set 16 0' command ? cause thats the correct one for the mogul/titan/6800
u probly already saw this but here:
http://forum.ppcgeeks.com/showthread.php?t=9229
info on ur problem.
i can actually say ive never heard of a case where it will exit the bootloader with mtty but everytime u soft reset it goes right back to bootloader. Get it loaded up and return that *****.