panther and internet sharing problem ?

[ibanez]

hi

im trying to share my airport internet connection on my powerbook with my other mac (g4 powermac) over ethernet.........

ive put my setting in the sytem prefs i.e
" share your connection from : AirPort to computer using : Built-in Ethernet ".

i have done this in the past with jag with no probs.

but still no luck on 10.3

any ideas ??????
thx