Under the code, Australia's 689 active ISPs and other groups providing e-mail services will share responsibility for helping fight spam. The companies must offer spam-filtering options to their subscribers, provide them with information about how to deal with spam, and have a process for dealing with complaints.

Intercontinental Hotel IT manager Ben Wrigley believes there has been a 100 percent increase in activity in the past 12 months despite the use of various software solutions. Wrigley blames the ease of use of downloading spamming tools, but says prosecution has become more effective.

He has looked at managed services, but says it isn't cost-effective.

"Through fine-tuning we have reduced false positives pretty much to zero," Wrigley added.

Western Australia's Curtin University of Technology senior systems engineer Kevin Manning said the problem got a lot worse before it got better.