virtualbox 4.0

[Minipot Gregg]

I wanted to get freeBSD but I didn't wan't to dual boot so I used virtualbox
4.0 and downloaded the ISO of the freeBSD amd64 8.2.
It installed fine but when I got to the boot menu and pressed [enter] x2 it
said CPU doesnt support longmode and then come's up saying type '?' to show
comands,
or 'help' to show help.
when I typed either of these commands it says '?' not found or 'help' not
found whats wrong and what should I do?