A new type of junk e-mail is puzzling to consumers. The e-mail, which is known as 'empty spam,' contains no recognizable marketing offers, viruses, or requests for personal information. Instead, the e-mail contains blocks of text from classic works of literature. In some cases, consumers see a combination of spam e-mail techniques. While similar spam has been seen in the past, the number of these empty spam messages has almost doubled in recent weeks. It now represents four percent of all spam e-mail, according to IronPort Systems, an e-mail security firm. For several days in June 2006, empty spam messages peaked at 40 percent of all spam. A number of explanations for the messages are beginning to emerge. According to one theory, spammers are trying to get around spam filters by confusing them. Spammers can embed passages of so-called 'hashbusting text' in their e-mails so the message passes through as legitimate. By sending spam messages comprised only of story text, spammers hope that users will report the messages as spam, throw the filters off, and make them less able to spot malicious messages later on. Another theory is that most spam filters are too advanced to be thwarted by this technique. According to Richi Jennings, e-mail security analyst for Ferris Research, empty spam is probably caused by a communication failure between the server originating it and the infected computers sending it.