To setup a standard POP3 email account on iOS 3 & 4, please refer to the following steps.

1.  Open the Settings menu and choose Mail.

2. Choose the Other option at the very bottom.

3. Choose Add Mail Account.

4. Enter the account information then choose Next.

5. Enter the account details, incoming and outgoing mail server information. Enter mail.yourcompany's website.com for both the incoming and outgoing mail servers. 

When the SSL prompt displays, choose Yes.

Return to the Email Account and choose the Advanced menu. At the bottom, change the server port
to 587.