Install FreeBSD on an external (usb) hard drive?

[Torfinn Ingolfsen]

Hi,

Is there a "trick" to installing FreeBSD on an external (usb) hard
drive?

I have just tried to install FreeBSD 6.2-beta1 (and 7.0-current 200609
snapshot) on an external (usb) hard drive which is connected to a
laptop. (Yes, the Acer AS5672 laptop, which have the ability to boot
off usb hard drives).

Installation went fine, and I installed the FreeBSD boot manager.
When I reboot, the boot manager comes up, but as soon as I press "F1",
the screen fills with what I think is register dumps (hard to tell,
because of the fast scrolling - and pressing "scroll lock" doesn't
work) and I must power off the machine to recover.

Any hints or pointers thankfully accepted.
-- 
Regards,
Torfinn Ingolfsen,
Norway