NEUSTADT, Germany (AP) _ Once a powerful knight clad in iron mail, Sir Friedrich von Kahlbutz now spends his days gazing vacantly from a glass-covered coffin rigged with burglar alarms.

He is a true scientific wonder, a puzzle that experts have studied but can't fully explain. While others decayed, Kahlbutz became a naturally occurring mummy. A bit thin, perhaps, but perfectly intact.

He fathered 41 children while he was alive but is even more popular in death, annually drawing tens of thousands of tourists to see the shriveled nobleman from a feudal era.

But now, Kahlbutz has become a prize in a very modern jousting match that has pitted church against state in this tiny east German town.

The mayor and the local pastor both claim ownership of the money-making mummy. At stake are enough tourist dollars to renovate a church or build a municipal parking lot.

''I will fight for my knight,'' declares Mayor Edmund Bublitz. ''He is very important to this city, a part of its history.''

''I don't care about the money, just the rights of the church,'' responds the Rev. Peter Freimark, the combative Lutheran preacher.

Kahlbutz was born to noble blood in 1651 in the old Prussian kingdom of Brandenburg. He died in 1702, the father of 11 children by his wife and 30 by peasant women in his domain.

He resides in a dank and chilly crypt where the stone walls are adorned with his helmet, breastplate and lance. He lies in his wood coffin, its lid replaced by plate glass, his body hooked to a wire that triggers a burglar alarm.

A caretaker flips on a tape recorder when visitors arrive, and a narrator tells of the battles he fought, the scientific studies that speculated on why his organs and skin did not decompose, and the offers from rich people - including a $3 million pitch from an American - to buy the ageless aristocrat.

Much mystery and legend, enhanced by the locals, surrounds the mummy.

''We have to clip his fingernails every week,'' contends a dead-serious Hildegard Mathiske, the caretaker.

One legend says the knight killed a shepherd who refused to subject his wife to the knight's ravishments. Kahlbutz supposedly denied the killing.

''If I am responsible let my body never decay,'' he supposedly said.

The mummy has been on public view since shortly after World War II, when the Soviet-held territory of conquered Nazi Germany was forged into Communist East Germany.

It is by far the biggest tourist attraction in this region 60 miles north of Berlin.

Tourism chief Georg Steiner says 100,000 people visited last year, many of them West Germans who began seeking out East German attractions after the Berlin Wall fell.

In July, three months before formal unification, East Germany and West Germany merged their economies and the powerful, convertible west mark became the official tender of the east.

The nominal admission fees went up, to $2.09 for adults and 90 cents for children.

Shortly afterward, the church filed a formal claim to the mummy, which is on the grounds of a small chapel run by the diocese.

Freimark said the church is best suited to safeguard the mummy. And, despite the urgings of his wife to be quiet, he accused the mayor of trying to sell the relic. The mayor denied this.

Both men have agreed to turn the matter over the city attorney, who continues to study the evidence.

Freimark's key evidence is a 1946 document from the Soviet-backed government of Germany's Brandenburg state, which deeded to the church the land where the mummy lay.

Bublitz, however, says that one of Freimark's predecessors relinquished in writing all rights to the knight during the 1960s. But he says the city can't find the letter.

Bublitz said he will let the matter drop no matter what the decision. Asked if he would press on if he lost, Freimark only smiled.

If he wins, Freimark says he will use the admission fees to renovate the main church in Neustadt.

Bublitz said the city will build a parking place to accommodate the tourists who descend on the town's cobblestone streets to gawk at the wizened corpse.