Firewire harddisk to boot my new imac

Hi,

I am new to mac, just get a I mac and wanna know if I can boot my imac by firewire external harddisk.

it is a external hardisk case + 7200rpm seagate 160GB harddisk.+ firewire,

what should I do?

format the harddisk and install mac system on it?

will it work?

if not, which firewire harddisk can do it?

Thanks



Thanks

yeah.. i think it should work.