Installing RH 6.1 using a pcmcia ethernet card seems not possible!? There is a pcmcia disc present but the installer never asks for it. Insted it asks for the network driver to use....
The new installer uses the pcmcia.img as the boot disk. You need to create a disk using that image and boot directly from it. In 6.0 you used the bootnet.img to boot and then it would ask for the pcmcia.img disk but that has changed for 6.1.