Bug 17761

greg lehey and i loaded 4.0 onto the third partition of a drive where
part0 was dos, part1 was bsd 3.4.  the installation of 4.0 proceeded
normally, and at the conclusion, the partition for 3.4 was missing and
its contents could not be recovered.

greg considered this a serious bug, and i have been trying to contact
him to find-out if the problem had been reported.  he's travelling, so
i'm mentioning this in his absence.

How-To-Repeat: i have not tried to repeat the problem.  

it may have been caused by mount points being named the same in different
partitions.  each of 3.4 and 4.0 had root and usr mount points.

here's how we did it:
partition a 4g drive with 4 partitions about 1g each.  install 3.4 on the second 
partition. create slices for root, swap, and usr (50m, 250m and balance).  
install 4.0.  create slices for root and usr (50m and balance).  you will
not be able to name the root / because the name already exists.  create
label /foo and then modify the name to /.  use a similar trick for /usr.
continue with installation.  

this must not be the correct way to install different versions and keep
them separated.  i sure would like to know how to do it.  

greg was jet-lagged from the trip up from australia, so maybe this is 
pilot error and he just didn't catch it.

bill