What does this PHP error mean?

[cmm14513]

I keep getting this PHP error while trying to connect to my mail server using POP3.

(ESMTP Exim 4.68 #1 Fri, 13 Jun 2008 21:20:27 -0500)

I contacted my hosting company and they changed there firewall and I still get the error. If maybe someone could just explain what the error means. It would help alot.
Im trying to get mail within an inbox, So im trying to login to the mail server and list all that is in an inbox. I cant even seem to login to the Mail server, I just get the error. Humm... Im really not sure whats happening.

[kevster1]

It's not a PHP error, it looks like a response from the mail server. You're trying to use PHP do retrieve your email? Or does your server use POP3 to send email? (And it probably won't relay, so it won't work. See if your host allows you to send mail through their SMTP server.)