IIS SMTP configuration settings

Question

I am using windows XP S2. I am sending email by using IIS SMTP. Now the problem I am facing is with SMTP server. All the mails I am sending are storing in SMTP Queue folder but its not sending them to the respective domains. I think that there is some SMTP setting problems, I need to configure SMTP. One more thing that I dont have any registered domain but i need to test application. So what are the configuration I need to make in order to test my application.

Thanks...