I have had the exact same problem, I disabled the spamcop plugin because the amount of bounces I was getting was getting extremely irritating.
________________________________ ---------- Forwarded message ---------- From: Axb <axb.li...@gmail.com> Date: 19 July 2013 15:15 Subject: Re: spamcop spamassassin reporting To: users@spamassassin.apache.org On 07/19/2013 04:00 PM, Giles Coochey wrote: Is there a current issue with reporting to spamcop? I got this response after reporting a bunch of spam: This is the mail system at host prod-sc-app10.sv4.ironport.com. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to postmaster. If you do so, please include this problem report. You can delete your own text from the attached returned message. The mail system <devn...@prod-sc-app10.sv4.ironport.com <mailto:devn...@prod-sc-app10.sv4.ironport.com> > (expanded from <spamassassin-sub...@spam.spamcop.net <mailto:spamassassin-sub...@spam.spamcop.net> >): unknown user: "devnull" deput...@spamcop.net will probably know more...