[otrs] pop access

I am constantly getting the following error sent via email. fetchmail: Server certificate verification error: self signed certificate fetchmail: Couldn't get service name for [pop@localhost] I have OTRS installed on OS X, and the mail server is on local host. How can I get it to accept a self-signed certificate? As for the second error, I assume that it is related, but I am not sure about it. I would appreciate any assistance. Thanks for your time in reading this.