I have the HWC54G PCMCIA as well, but can not get it to work running Knoppix 3.8:

# lspci-v
Network controller: RaLink Ralink RT2500 802.11 Cardbus ReferenceCard (rev 01)
Subsystem: Edimax Computer Co.: Unknown device 0c54
Flags: bus master, slow devsel, latency 64, IRQ 11
Memory at 0c000000 (32-bit, non-prefetchable) [size=8K]
Capabilities: [40] Power Management version 2

If you find any info, drop me a line. Thank you.