In a simple twist of tactics, spammers are sending large amounts of unsolicited e-mail that has been date stamped one month in the future -- in order to guarantee their messages remain at the top of the recipients' inbox.
This twist is another advancement in the ongoing battle between spammers and the anti-spam filtering firms.
Joel Camissar, country manager at Internet security firm Websense, said the change in tactics may be a simple one, but it has proven to be effective.
"I am surprised at the simplicity and that it hasn't been tried before, but it is often the simplest ways of beguiling users that can be the most effective," Camissar told ZDNet Australia.
In this latest attack, a large number of e-mails -- in this case mainly advertising weight loss products -- each seemingly from a different sender and with different, yet related, subject lines, take the top spot in the recipients e-mail inbox.
According to Camissar, this trick is likely to confuse a significant number of people.
"Especially if you have your dates configured in American format -- as so many companies do," he added. "[The recipient] may not even realise why they stay at the top of their e-mail inbox."
Phishers spoof MySpace "friend request" e-mails
In other security news, users of MySpace have been targeted with phishing e-mails that seem to be from another member of the social networking site asking to be added as a "friend".
Camissar said that MySpace has increasingly become a target for phishers: "This is one we have seen quite a lot.
"If you follow the link it takes you to a spoof MySpace.com log-in page; it then captures your account information and then forwards you to the real MySpace.com Web site," he said.