a few minutes ago, i tried to connect an external hd using a firewire 400 cable to my mbp(10.5.6) and it wouldn't mount. all i got was a beach ball in finder. the same external hd worked just fine using usb and firewire 800. it also works fine on my imac g4 running 10.4.11 through the fw400 cable. is this some kind of incompatibility with leopard?