enabling smtp

[rollo tamasi]

I have installed Roundcube on my server and it's receiving email but i can't send email.

In the config file it requires a smtp address. I entered in smtp.website.com but i'm not sure if that is correct.

I have not setup anything smtp related within plesk.

Any ideas on what i need to do.
I do have a MX record setup for mail.website.com but that's it.

Thanks