wpasupplicant indeed had a driver backend for rt2500 based cards, but this backend never really worked and was therefore disabled in the package. You can try to recompile wpasupplicant with that support, but don't hope too much.
The only real solution at this point seems to me to either make rt2500 provide the needed extensions or to switch to rt2x00, which is a dapper+1 think. IOW: I don't see wpa support for rt2500 based cards in dapper. Sorry.
wpasupplicant indeed had a driver backend for rt2500 based cards, but this backend never really worked and was therefore disabled in the package. You can try to recompile wpasupplicant with that support, but don't hope too much.
The only real solution at this point seems to me to either make rt2500 provide the needed extensions or to switch to rt2x00, which is a dapper+1 think. IOW: I don't see wpa support for rt2500 based cards in dapper. Sorry.