Use the regular SMTP Relay Server for GoDaddy: relay-hosting.secureserver.net
Here is my configuration lines (Notice that: my admin email address is not even a real email address), ~line 172~
<add name="SystemMailProvider"
type="Subtext.Framework.Email.SystemMailProvider, Subtext.Framework"
smtpServer="relay-hosting.secureserver.net"
username=""
password=""
adminEmail="admin@YOUR DOMAIN NAME.com"
/>
<!-- NEAR LINE 310 - NOTE: This is that I get my comments on. -->
<add key="HostEmailAddress" value="HOST-EMAIL"/>
After this, it does work. However, I warn you not to type in your own address. For some reason trying to send yourself an email doesn't work too well.