Sydney  - A relative of the Aboriginal author whose image appears on Australia's 50-dollar notes reckons he's owed millions of dollars in royalties because the person who gave permission for the imprint was an impostor.

It's a complicated case that could be settled easily, if David Unaipon's family were DNA fingerprinted.

However, that is unlikely to happen - and it might even be illegal under draft legislation before parliament.

The government wants to make it illegal to conduct a genetic test on a sample obtained without consent. It would also be illegal to disclose the results of a test carried out surreptitiously.

Taking DNA samples without permission is already a criminal offence in some countries. A lobby group for disgruntled men is opposed to the law that would forbid taking a few strands of hair or some saliva for testing to establish the paternity of a child.

"There's no reason why someone who wants a DNA test on their child shouldn't be allowed to do so," Fairness in Child Support spokesman John Flanagan said. "Why should fathers have their lives ruined by having to pay tens of thousands of dollars for someone else's children?"

Paying maintenance is a hot issue. By one estimate, 254,000 men owe the mothers of their children a combined 1 billion Australian dollars (640 million US dollars) in unpaid child support.

Flanagan's group makes much of the case of Liam Magill, awarded the equivalent of an average annual salary after genetic testing determined he was not the biological father of his youngest two children. Magill took the initiative, took samples, and took them to a private testing service. He then went to court.

Stories like Magill's are not uncommon.

Ten years ago, Martin Hunt thought he had got his girlfriend pregnant. They broke up before the baby was born but he continued to pay child support. He collected a DNA sample and found the boy was not his.

"I believe DNA tests should be mandatory at birth for all parties," Hunt said. "It would stop the lying."

Of course, it could also create enormous societal disruptions. (dpa)