He wants to use the pontiff's first state visit to his home country Germany this week to demand justice, accusing him of deliberately turning a blind eye to the suffering of abuse victims.

"After a holiday spent at a Catholic camp, Father Peter Hullermann suggested to my parents that I sleep at his home on weekends," Fesselmann, now 43, told AFP. "I was so cute."

Coming from a deeply religious family, the altar boy felt comfortable chatting and watching television with the cleric, who was popular with youths for his mesmerising sermons. But one night, he said, the attention turned sinister.

"He served me alcohol. I had to tell him the names of my genital organs which of course excited him. He then ordered me to undress, to masturbate, then to perform oral sex on him."

On returning home, Fesselmann became sullen and reserved and refused to go to church. Three weeks later he confided in his best friend.

"I wanted to protect him," he said.

His friend's parents reported the abuse to the Church, leading to the priest's transfer from the western city of Essen to Munich in the south.

However Fesselmann's family refused to believe him.

"I do not want to hear about it as long as I live," his mother told him.

Fesselmann obeyed, waiting until her death in 2000 to confront his repressed memories.

Since that time, the father of three suffered panic attacks, lost his job and even tried to commit suicide. But then he decided to fight.

"It was Joseph Ratzinger as Archbishop of Munich in 1980 who signed my priest's placement papers," Fesselmann said. "If you sign such a document, you know what it means."

In June 1986, Father Peter Hullermann was sentenced to 18 months suspended sentence on several counts of sexual abuse.

In March 2010, when the case was exposed in the US press, the vicar general of Munich at the time, Gerhard Gruber, assumed "full responsibility" for reassigning the cleric, calling it a "serious mistake".

However Fesselmann wants Benedict to accept personal responsibility for his ordeal and that of the other victims.

"It was always the same story in different countries: the paedophile priests were moved elsewhere," Fesselmann said.

In May last year, he wrote asking to meet the pontiff during his stay in Germany. He was told three months later that his request for an audience would be reviewed but since then he has had only silence from the Vatican.

"I find this very disappointing because he's a German pope, and he should deal with victims in Germany first. He met with them in Ireland, why not in Germany?" Fesselmann asked.

Unable to meet with Benedict during his stay in Berlin on September 22-23, Fesselmann plans to demonstrate in the German capital with the US-based Survivors Network of those Abused by Priests (SNAP), to which he belongs.

SNAP last week asked the International Criminal Court to prosecute Benedict for crimes against humanity linked to sexual violence committed by clergy around the world, in what observers said was a largely symbolic move.

With such actions, Fesselmann says, "we want more and more victims to step forward, we want to encourage them to break their silence."

The paedophile scandal in the Catholic Church exploded around the turn of this century with thousands of revelations of sexual abuse by priests in the United States.

The deluge of subsequent allegations in countries around the world led the pope to express his "shame" and to pledge Church action against predatory clergy.

The Vatican said last week that it would not rule out a meeting between the pope and abuse victims during his stay in Germany.

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