SYDNEY: Australian band Men at Work were found guilty Thursday of plagiarising children's ditty "Kookaburra" in their 1980s hit "Down Under" after a court battle involving two of the nation's most iconic songs.

Federal Court judge Peter Jacobson found a flute riff in "Down Under" bore an unmistakable resemblance to "Kookaburra Sits in the Old Gum Tree", a four-bar folk tune taught to Australian schoolchildren for 75 years.

Music company Larrikin, which in 1990 acquired the rights to "Kookaburra" -- penned by teacher Marion Sinclair for a Girl Guides Jamboree in 1935 -- stands to gain royalties and compensation for the worldwide hit.

"I have come to the view that the flute riff in Down Under in the 1979 recording and 1981 recording infringes on the copyright of Kookaburra, because it replicates in material form a substantial part of Ms Sinclair's 1935 work," judge Jacobson ruled.

Though it had a markedly different "feel" and musical context in "Down Under", Jacobson said the riff was an iconic Australian melody and had been "substantially" reproduced by Men At Work.

The judge said it was clear that band member Greg Ham had deliberately plagiarised the tune "for the purpose and with the intention of evoking an Australian flavour in the flute riff".

"Mr Ham looked for a complementary part for his instruments, and especially one which fell into the 'tongue-in-cheek' nature of the song. He described the flute line as 'an Aussie cliche melody'," Jacobson said.

He pointed to the song's video, which shows Ham playing the melody in a tree, and evidence that Men At Work sometimes substituted the flute solo for singing the "Kookaburra" words at their concerts.

He said the riff was what made "Down Under" instantly memorable and recognisable, but Larrikin was entitled to an as-yet-undetermined amount of royalties and compensation from Men At Work and music labels Sony BMG and EMI.

"It's a big win for the underdog," Larrikin's lawyer Adam Simpson told reporters outside court.

Simpson said Larrikin would be pushing for the labels and songwriters Colin Hay and Ron Strykert to hand over between 40 and 60 percent of their earnings from the song. A costs hearing will begin on February 25.

EMI's John Anderson said the company would need time to consider what he dubbed a "complex judgment", adding that significant damages would "not necessarily" follow the ruling.

"Down Under," an unofficial Australian anthem and jukebox staple worldwide, sold millions of copies across the globe, and was also the theme tune for the victorious 1983 Australian team in yachting's Americas Cup.

The song, which featured at the close of the 2000 Sydney Olympics, pays tribute to Vegemite sandwiches and a land where "beer does flow and men chunder (vomit)".