I've got the Acer 7220 and faced the exact problem as you. Get the Leo4All distro and apply the PPF-patch with extensions pack 2 (google is your friend, search and you will find). Then get the iDeneb combo update 10.5.8 and there you go! The only thing that doesn't work is graphics hence to the Geforce 7000M (1024x768). Wifi, Atheros 5007EG works whenever it likes so use cable instead.
Actually, the whole experience, in my opinion, suffers a lot when graphics is limited, as my screen is capable of 1440x900.

Cheers and good luck!