Below is a sample of how to do fake players for CoD2. Thanks to DPGmaximus for letting me use his cd key to test with.
It's quite similar to CoD4. As usual, my example is in PHP and meant for command line usage only, but feel free to port it to whatever language you desire. You must run the script like so: file.php server port cdkey
"cdkey" must be in CAPS, without dashes. You can use the full cdkey, or the first 16 characters of it... doesn't matter. The PBGUID variable in the script must be manually changed to the GUID of your cd key. You can find your GUID by using Luigi's key2pb tool like so: key2pb ABCD1234ABCD1234 0x00b684a3. Please note, you must also use the first 16 of the cdkey, all caps, no dashes.Reply from the script and its meaning:
. - fake player added
F - server is full
? - server replied with nothing
T - timeout
I - cdkey reported in use
N - master server needed getKeyAuthorize string sent again, so it was sent again
C - server said the challenge was bad
If there are any unhandled replies from the server I didn't get (I'm sure there are more) post them here and I can include them in the script. This is just a basic example though.