this is quick and dirty howto.
it's tested and work out ok on my system. but i dont guarantee it wont break yours.

these are the 5 easy steps:
1. enter yourdomainname.com in ipcop's dhcp service
2a. create dns record to point wpad.yourdomainname.com to your ipcop ip. or,
2b. edit /etc/hosts and put 'wpad 192.168.1.1' into a new line. replace 192.168.1.1 with your ipcop's ip
test it by ping wpad and see if it resolve to your ipcop's ip
3. create the wpad.dat file in /home/httpd/html/
4. add 'Listen 80' to a new line in /etc/httpd/conf/httpd.conf
5. restart apache: 'kill -HUP 1234' replace 1234 with your /var/run/httpd.pid

test it by opening http://wpad/wpad.dat in your browser

that's it! your browser now can automatically detect your proxy setting.