You can check the compiling section of the howto, here's a quick summary:
1. Install the kernel source pkg that matches your `uname -r`.
2. download the pre4 source tarball here: http://rhlx01.fht-esslingen.de/~andi/acx100/ and follow instructions on that page to unpack
3. browse your windows install disk looking for the *.BIN files, they are listed in the README file that gets unpacked in the top-level acx100 directory, in this case you are looking for something besides what you already have, or at least of a different filesize.
4. copy those firmware files to the firmware directory under the top level source directory, ie: acx100-0.2.0pre4/firmware, and also to the directory you're passing to modprobe in either the options acx100_pci line in modules.conf or on the command line.
5. in the top level directory type "make", wait for it to compile.
6. acx100_pci.o will be in the src/ directory, copy it over top of your existing acx100_pci.o
7. ifconfig eth1 down, rmmod acx100_pci, modprobe acx100_pci
8. make sure for pre4, you do not use the channel parameter to iwconfig, you need to comment it out of any scripts and not use it on the command line either.
9. iwconfig should now show 0.2.0pre4 in the upper left.

Ok, this may take several tries, my best guess is to try the maxim radio module first, so rename APLUSMX.BIN to WLANGEN.BIN and just use that one firmware file for both compile and load. If that doesn't work, delete WLANGEN.BIN from both places and try renaming AIRPLUS.BIN to WLANGEN.BIN and compiling/loading with that file instead.

I extracted/installed the kernel source, after downloading the pre4 source. Copied the firmware from my drivers cd into the firmware directory and ran make from the root acx100 dir.

I'm installing the compiled driver and firmware now.

I wasn't sure how to reset iwconfig so I rebooted. The nic led doesn't stay lit unless there is activity unlike it's windows counterpart. How ever it does work. The firmware must have been the problem. There were a few dmesg errors I'll tack those on after this.

eth1 Link encap:Ethernet HWaddr 00:80:C8:04:50:C1
inet addr:192.168.1.20 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:576 Metric:1
RX packets:1036 errors:0 dropped:0 overruns:0 frame:0
TX packets:247 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:110222 (107.6 Kb) TX bytes:21192 (20.6 Kb)
Interrupt:10 Base address:0xff80


eth1 v0.2.0pre4 ESSID:"Toys"
Mode:Managed Channel:11 Access Point: 00:40:05:5D:34:43
Bit Rate=5.5Mb/s Tx-Power:18 dBm
Encryption key:F0AB-2B8E-A3 Encryption modepen
Link Quality:100/100 Signal level:74/100 Noise level:0/100
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0

root@extra:~# ping -c 4 www.google.com
PING www.google.akadns.net (216.239.39.99): 56 octets data
64 octets from 216.239.39.99: icmp_seq=0 ttl=46 time=39.2 ms
64 octets from 216.239.39.99: icmp_seq=1 ttl=46 time=38.8 ms
64 octets from 216.239.39.99: icmp_seq=2 ttl=46 time=40.6 ms
64 octets from 216.239.39.99: icmp_seq=3 ttl=46 time=41.5 ms

dmesg errors

acx100: It looks like you were coaxed into buying a wireless network card
acx100: that uses the mysterious ACX100 chip from Texas Instruments.
acx100: You should better have bought e.g. a PRISM(R) chipset based card,
acx100: since that would mean REAL vendor Linux support.
acx100: Given this info, it's plain evident that this driver is EXPERIMENTAL,
acx100: thus your mileage may vary. Visit http://acx100.sf.net for support.
acx100: form factor 0x00 (standard?), radio type 0x11 (RFMD), EEPROM version 0x0004. Uploaded firmware 'Rev 1.9.3.e' (0x01020505).
acx100_issue_cmd failed: Invalid parameter [150250 uSec]
acx100_issue_cmd failed: Invalid parameter [150050 uSec]

Well, I don't know what was going on, I'm glad it's transmitting now, but it makes me wonder since I've got the exact same EEPROM line in my log as well, same firmware revision, same 0x01020505. Must be compiling it on your machine was the fix, it's best that way anyway. Which firmware file did you end up using/renaming?

As for the errors, I'm really not sure whether they are "normal" or not, try setting your rate to 22M, also I'd be curious what txpower 40 does for the card although you don't really have any signal problems.

I copied all the .BIN files from my cd into the firmware directory the compiled. After that I just did what the instructions said to.

txpower 40 was already in the activation script. I changed the rate to 22M, however it doesn't seem to have effected anything.

You're saying you didn't have to rename anything to WLANGEN.BIN? If so, that is odd, that comes right out of their README...

oops, I didn't read the readme I just followed the howto instructions.

Edit:
I used these files as they were

AIRPLUS.BIN* AIRPLUS.INF* APLUSGEN.BIN* APLUSRFM.BIN*
AIRPLUS.CAT* AIRPLUS.SYS* APLUSMX.BIN* APLUSRMX.BIN*

There is only one thing I can think of. I forgot to remove the old firmware from the systems acx100_fmwe directory. so that is probably how it is functioning.

just noticed this message. I must have responded before it showed up.

Well that explains why we both have that same EEPROM line, your firmware files never got used. I've got to add something to the howto about renaming them, but since they are vendor specific it's going to be difficult to say which files should get used and renamed...*scratches head*. I'd be curious if you rename AIRPLUS.BIN to WLANGEN.BIN and recompile as well as putting that same file(WLANGEN.BIN) in your acx100_fmwe directory what happens.

Do you know of any sites that provide a list of supported wireless cards? In the future I plan to buy atleast one more, and it would be nice if supported by the mfg.

That's a question that's asked here quite a bit, it's difficult to answer since chipsets in the devices change fairly frequently and model numbers don't seem to change that much with them. You end up on the phone asking a rep to read you things off the box (which they can't do) or asking for the "older" version of a card and having them send you the newer one anyway, this is how I ended up with so many wireless cards. The d-link dwl-650 is a prime example of this, when you go to their site to get windows drivers they show you pictures of at least 3 different cards all with nearly the same model number, then you pick the one that yours looks like. The good news is that they've all eventually worked.

that said, here's a link to a rather extensive listing:
http://www.linux-wlan.org/docs/wlan_adapters.html

Thanks, if nothing else I'll have to do a bit more searching on the net for comments on a card before I buy it. Although it was hard to resist these cards. They were about $15 after a mail in rebate. So I guess I got what I paid for

Well, I wouldn't mind having one just so I can speak intelligently about it when people ask, so if you'd like to sell one I can email you payment via paypal, let me know...don't post any personal info here, use email