While the Netgear isn't supported by any free Linux drivers that actually seem to work (there are pay-for ones that do), I can't think of any reason why any wireless device wouldn't support IPX/SPX.

Since Novell 4.x doesn't support TCP/IP (at least not very well, if it does at all) for client connections, I installed the Novell client using the option for IPX/SPX only. It Just Works. Has since day one.

Assuming I replaced the Netgear card with another one supported by default in Linux, I'm 99% sure I should be able to connect to the Novell 4.x server without incident.