Step 1: Open Entourage.

Step 2: From the Tools menu, select Accounts, that brings up the Accounts window.

Step 3: Double-click on the email account that is listed on the Mail tab, that brings up the Edit Account window.
(If you don't have an account listed on the Mail tab go to the New menu and choose Configure Account Manually).

Step 4: From the Account type pop-up menu, select POP. and click OK

Step 5: In the Edit Account window, enter the following:

Account Name: your Email/Reply-to Address or other convenient identifying moniker
Check Include this account in my "Send & Receive All" schedule
Personal Information
Name: Your name, the way you want it to appear on your email
E-mail address: your E-mail Alias or Email/Reply-to Address from your Account Information
Receiving mail
Account ID: your Email Account/POP Username from your Account Information
POP server: mail.yourdomain.com
Sending mail
SMTP server: mail.yourdomain.com

Click OK, your done!