i've been trying to mount the generic-pc-1.3.img under linux as per:
http://www.linuxquestions.org/questions/debian-26/how-to-mount-freebsd-partition-from-debian-gnu.linux.-etch-4.0-583605/

mount -o loop,ufstype=44bsd -t ufs generic-pc-1.3 /mnt/m0n0

i've experienced the same problems as the users in the above link.  bad
magic number.

i poked around quite a bit, tried different versions of linux (ubuntu,
insert) and the result is the same.

years ago, i had succeded in mounting the image under slackware using the
above technique.

on a hunch i tried the same with 1.2... works just fine!

so looks like the problem is that something has changed between 1.2 and 1.3

anyone have any idea how to mount the 1.3 image?

jj