Make sure you have DavMail running.
In iCal, go to Preferences in the menu. Click tab Accounts. Click + to add a new account. Choose CalDav from drop down list as account type.
Enter username and password. For the username, add username only, and not domain\username.
As server, add something impossible like ‘loca’.
The software will complain after you click Create. Ignore this warning, and click Create again. This will open a more complete entry form. This time, enter
- Server: ‘localhost’
- Server path: ‘/principals/users/<your email address>/’
- Port: 1080
- SSL: leave unchecked
You should now see your Exchange 2003 account appear in iCal.