For everyone out there who still didn't figure how to hack the BM yourself.
Here it comes. Just copy the BOOTMENU.PBT to your BM folder and that's it. BM now loads all backups. But you can't load backups without BM, cause it's no firmware hack.
best regards Jones23
EDIT: A full firmware and Bootmanager hack can be found here in the forum. (you'll have to register to view attachments)