Virus Bulletin has found that enterprise spam filters are blocking less and less junk mail.

"During a comparative of 20 corporate email filtering products, several missed more than twice as much spam as in previous editions of the VBSpam tests," writes The Register's John Leyden. "Virus Bulletin reckons the drop in performance might be down to improved tactics by spammers rather than a dip in the capabilities in the filtering products it put through their paces."

"The best performance in the March 2012 anti-spam comparative review came from Libra Esva, which blocked 99.97 per cent of all spam messages without blocking any legitimate mail, making it the only product to obtain the new 'VBSpam+' award," Leyden writes.

Go to "Report: Feeble spam filters catch less junk mail" to read the details.

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