Spam-filters bounce email about spam-filters

Spam-filters are trained to catch anything that looks like spam, including discussions of spam and spam-filters.
"Patterns of e-mail use are definitely being impacted both by spam and by antispam filters," said Craig Hughes, chief architect at McAfee Security and co-developer of the open-source SpamAssassin spam-filter project.

"I myself run into the problem all the time, mainly because what I'm corresponding about frequently involves discussions of spam or particular spam strategies..."

"I've lost count of the number of e-mails that get bounced back thanks to spam filters getting triggered by completely innocent words and phrases," said Suresh Ramasubramanian, head of security and antispam operations for managed mail-services firm Outblaze.