My task is very typical. I get an email from the user through the html form and need to send him a confirmation to his email address. I tried it to do using sendmail and SMTP package but my web host provider server does not allow popular address like yahoo, gmail, etc to be sent protecting ftom malicious software. So, please share your experience what you do to send emails to an arbitrary address. How is it implemented in the forum software which send private emails, for example?