Trying to install the BC4401 nic card on Redhat 7.3.

rpmbuild -bb SPECS/bcm4400.spec

Getting quite a few errors, including
gcc -DMODULE -D__KERNEL__ -DDBG=0 -Wall -Wstrict-prototypes -06 -I/lib/modules/2.4.20-287/build/include -c -o b44um.o b44um.c
/usr/include/linux/interrupt.h:44:25: asm/hardirq.h: No such fiile or directory
/usr/include/linux/interrupt.h:44:25: asm/softirq.h: No such fiile or directory
In file included from /usr/include/linux/highmem.h:5,
from /usr/include/linux/skbuff.h:5,
from b44mm.h:53,
from b44um.c :57:
/usr/include/asm/pgalloc.h:6:24: asm/fixmap.h No such fiile or directory

Other files not found:
asm/delay.h
asm/uasccess.h

Note this is hand typed (rather then cut and paste), due to the remarkable difficulty of transferring data from a computer that has no nic, no floppy, and no CD-R.

Help a newbie out.. Am I in source hell right now?

This probably isn't helpful if a change of distro is out of the question, but I have the same NIC and it's worked without any fiddling on Fedora Core 1 and later, and also on Slackware 10.0.

I found the solution to my problem.
To compile drivers, apparently you need the kernel source installed.
I simply installed the kernel source rpm, then compilation went without a problem.

Ran insmod bcm4400, then rebooted to allow kudzu add it to my modules.conf file