In one of our jobs we use xp_smtp_sendmail to send some attachments.

I used my name as the sender and receipient. I set the server as my email server. I got the mail. But if I use different servername the email is not coming. But the problem is if the receipients and sender are on different servers the eamil is not going.
I tried to add two server names in the server parameter for this procedure. I am getting error message. Could we add multiple servernames? How to resolve this.
Please advise.
Thanks