Craig Warren, Deakin's operational service provision manager, said the Linux servers running antivirus and spam filtering software were effective for about three years, but "the spammers were steadily beating us".

As a result the university has implemented two IronPort c300 e-mail security appliances.

"We were continually spending time fine-tuning our detection and prevention, but the intruders were quicker than we were," Warren said.

Another organization that recently implemented IronPort is the CSIRO with IT security operations manager Tom Minchin confirming the science agency dumped its antivirus vendor Trend Micro in the process.

Enterprises claim they are losing their trust in e-mail as scams, spam, viruses and phishing continues to undermine its business value.