Mylex DAC1180 booting problem

[Oliver Neubauer]

Hello all,

I'm having a tough time getting a new FreeBSD 5.2 installation to boot 
off of a RAID system drive (Mylex DAC1180, two RAID 5 system disks 
defined, 2G mode).

Essentially, I have done a standard install, creating a FreeBSD slice on 
the smaller (5G) system drive (using the whole disk, non-dd mode) and 
even created a separate partition on that slice for /boot (200M).

When I reboot the system, the boot screen  says it can't find /boot or 
kernel. I suspect this is largely due to the fact that it seems to be 
looking on ad0a instead of mlxd0d since it's displaying something like 
0:(ad,0)/boot

I hate to sound like such a newb, but my attempts to change the loader's 
default is falling well short of producing any results. So I guess my 
direct questions are:

How can I use the (horribly crippled, it seems) virtual shell from the 
installer to modify the boot loader's behavior via boot.conf (mounting 
the disk is the problem here).
and/or
How can I make it look for /boot on another device at boot time?

Anyone have any helpful advice?

Thanks
Oliver