SMTP over msn dial-up

[eclipsed]

I need to be able to send email from my machine, but I seem to have a few problems.

1. I connect to the outside world via MSN (aka Satan)
   
2. My email account is with yahoo, which as of recent have stopped offering free SMTP services.
   

So, the problem is I can't send email (unless I use yahoo's web UI, which is what I'm trying to get around) from my box. MSN has a server at smtp.email.msn.com, but I can't get properly logged in. They use SPA so it seems that normal SMTP-AUTH will not work. (Trust me, I've tried). I tried using an account with softhome.net, but they won't send my mail because their servers block it due to the relay (fuck spammers, they've trashed email and turned it into a security nightmare). I suspect that if I ever did get auth'ed with MSN that I'd have the same problem. I've looked into rewriting the headers, but have only found info on this for Sendmail. I thought I'd found the solution w/ nbsmtp, but it still requires an outside SMTP server. So, can anyone offer me a solution that will allow me to send email from my Yahoo account via a real MTA, not their web UI. TIA.
-Adam