Unable to send mail?

[trekkie2444]

I keep getting this in my error log:

http://e-p1.net/index.php?pretty;action=reminder&sa=picktype;PHPSESSID=ae796bfcc724c3b0a8b9a69a73fd1b91Unable to send mail to the email address '[email protected]'

http://e-p1.net/index.php?pretty;action=register2Unable to send mail to the email address '[email protected]'

http://e-p1.net/index.php?pretty;action=pm&sa=send2Unable to send mail to the email address '[email protected]'

[Deaks]

do these addresses actually exist, is it only these three addresses or is it more