Pegasus Mail 3.1

To configure SMTP AUTH in Pegasus Mail 3.1 you have to select item "Internet options..." in the "Tools" menu. Like on the picture below.

    

Then, a preferences window will appear. You should select "Sending (SMTP)" tab. The window will then look like on the image below.

    

Select "Login using my POP3 settings for username and password". Click "OK" to complete the change.