yeah, here's how it'll work:
sl5500+wlan card : on the internet already, no sweat.
<---- serial cable ----> gp2x : needs my new kernel, pppd, and a script
the gp2x connects to the sl5500 over serial, establishes a ppp connection, now has its own little 'network' between the sl5500 and itself. the sl5500 then acts as a bridge to the WLAN, and oila: the gp2x has itself some internet love!
lets see if i can get it working this week, just for the fun of it .. but if it does work, its (to me) a viable way to get gp2x network gaming up and running, for those who have the hardware ...