Problems installing 6.2 on Core2Duo (Intel P965): can't mount root filesystem

Sat Apr 21 14:48:40 UTC 2007

Hi, I've run into some problems installing FreeBSD 6.2 on my Core 2
Duo machine equipped with a MSI P965 Neo motherboard with a Jmicron
361 RAID PATA/SATA controller, and an Intel ICH8 SATA controller. The
PATA cdrom is connected to the Jmicron controller.

It seems like all the disks are detected (including the PATA cdrom
drive), as the kernel spits out something along the lines of:

ad4: 305245 MB <WDC WD3200KS-00PFB0 21.00M21> at ata2-master SATA300
acd0: DVDR <TSSTcorpCD/DVDW SH-S182D/SB04> at ata3-master UDMA33

Just after these two lines of output are printed, I get presented with
the mountroot> prompt asking me to manually specify the root
filesystem.

Any suggestions on how to fix this?