Firewire old and newer imacs

[oisin10708]

What Firewire cable should I use to connect an old iMac (Powermac G4,2 serial QT212KDMLF4) to a newer iMac (10.1 Serial W89405HDB9U). The ports look different. A online mac store told me a 6 pin to 9 pin but it would take 4 months for me to get. Would buy from abroad but not sure which Mbits/sec (400 or 800) I should be looking for.
PoweMac's port shaped uptight rectangle with rounded base, larger than other computer's and eith centrally placed white ?pins - perhaps 3 each side, other computer has a rectangle with apparently 2 sets of pins - probably 4 and 4 a side.
Thanks,

Catherine