hcfpcimodem and x86_64

I have a 56K modem that works with the hcfpcimodem driver on my old computer.
I just bought an Athlon 64 and installed Fedora Core 5 for x86_64 and wanted to
transfer the modem to the new computer.

I didn't see any pre-built rpm's for the x86_64 architecture.  I tried installing the generic
'tar' file, but when it compiles it gives a bunch of warnings that it is not likely to work.
And of course, it did not work.

Any suggestions?

Thanks!

Bev