How to send emails from an address without logging into the server

I'm building an asp.net application for a client that requires a c开发者_JAVA百科onfirmation email to be sent. I've gotten the code working but the only problem is that I can't get the code to work with their web host (godaddy). Is there a way to send emails with the from address marked as the clients' without having to use godaddy? (essentially faking it)

Be careful or you'll lose your emails to spam filters.

Specifically, see the Reverse PTR record discussion here:

http://www.codinghorror.com/blog/2010/04/so-youd-like-to-send-some-email-through-code.html