* Catholics say expect no breakthroughs on divisive issues
* Protestants want Benedict to allow joint communion
* Idea of pope as all-Christian spokesman opposed
By Tom Heneghan, Religion Editor
PARIS, Aug 29 (Reuters) - Pope Benedict will honour the 16th century Protestant reformer Martin Luther on his state visit to Germany next month, but Roman Catholic officials are warning Lutherans not to expect breakthroughs on issues dividing them.
During the Sept 22-25 visit, the German-born pontiff plans to stress ecumenical cooperation, meet Protestant leaders and tour a monastery in Erfurt where Luther once worked and prayed. He will also address the German parliament in Berlin.
The visit has prompted calls from Protestants for him to allow joint communion services and grant their churches full recognition. The tone is mostly positive -- one theologian even suggested making him "honorary spokesman" for all Christianity.
But senior Catholic clerics have begun warning Protestants not to get their hopes up too much.
"Hopes about this visit have gone wild," Rev. Hans Langendoerfer, secretary of the German Bishops Conference, said in Monday's edition of the weekly magazine Focus.
"There's talk Pope Benedict could grant the Protestants a new status or could just say 'OK, let's completely change those rules about communion services. It doesn't work that way."
Catholic Bishop Joachim Wanke of Erfurt said last week that Benedict's meeting there with Protestant leaders in the St Augustine Monastery could foster closer ties, but also ruled out any breakthroughs on basic differences.
VATICAN OPPOSES JOINT COMMUNION
Luther was a Catholic monk who sparked the Reformation in 1517 by challenging several doctrines and Vatican corruption.
After he was excommunicated, he established his own church, allowed clergy to marry and translated the Bible into German. Other dissenting Christians elsewhere followed his example, launching a wide range of Protestant denominations.
Catholics make up just over half the world's 2.2 billion Christians and Protestants about one-third.
Relations have improved markedly in the past 50 years, with growing Christian cooperation as Western societies become more secular and Islam spreads beyond its traditional regions.
But the Vatican rejects calls for joint communion services, saying theological differences about the eucharist are still too great, and Benedict annoys Protestants by saying they don't have proper churches but only "ecclesiastical communities."
"I'd be very happy if the pope ... recognised Protestant churches as proper churches," said Ilse Junkermann, the female Protestant bishop of Erfurt who will host Benedict's meeting with Protestant leaders at Luther's old monastery.
She told the Evangelical Press Service (epd) that Christians had to work together in eastern Germany because so many people there were atheists after four decades of communism.
FOCUS ON THE POSITIVE
Langendoerfer said Benedict would honour Luther's contributions to Christianity such as his emphasis on the Bible and promotion of popular piety.
"In Erfurt, Benedict will aim to get further away from the idea that Protestants are first of all dissenters," he said. "This broad view of Christian history could be very fruitful as we approach the 500th anniversary of the Reformation in 2017."
Catholics and Lutherans, who reached a conciliatory new view of their original disputes in 1999 and lifted the mutual condemnations issued during the Reformation, hope to come closer with a joint statement on the 500th anniversary of the split.
Lutheran theologian Reinhard Frieling got a bit ahead of the game this month when he wrote: "The dream of the unity of all Christians can be realised if Protestants grant the pope the role of the honorary head of Christianity."
After other Lutheran theologians protested that that went too far, he said he wanted unity "with but not under the pope" and the pontiff could speak for all Christians only after consulting the non-Catholic churches. (Editing by Matthew Jones)