Norwegian rocker Roger Tiegs has been found guilty of aggravated sexual assault, but cleared of raping a woman - a year after he was jailed.

Tiegs, known by fans of his band GORGOROTH as INFERNUS, was sentenced to three years in prison last year (05) along with another, unnamed, man for an attack on a 29-year-old woman.

But a Bergen appeal court concluded there is no evidence to support the rape charge against Tiegs, while upholding the conviction against his friend.

Tiegs' lawyer Egil Horstad is baffled by the appeal court jury's decision.

He says, "It's difficult to understand the jury's thought process when they find my client guilty of aggravated sexual assault.

"First they state that my client wasn't involved in the rape of the woman, or that he even knew that a rape had occurred. Then he's punished because he should have realised what had happened."