Were you ever able to contact your host to ask about an SMTP server? Your host should provide you with one you can use that does not require authentication. The gmail and hotmail servers will definitely require authentication.
The reason why authentication is not supported is because it is a limitation of the php mail call. In order to use authentication the server must have PEAR support with mail available. You could use Universal Email to configure the email to use the authentication settings, but you will still need a valid value for the mail server. If this value is not known to you then you should contact your host and ask for details.