The Muslim in question, Muhammad Kalisch, is said to support the work of another German academic who has suggested “that the Koran is a Christian text and that Muhammad probably never lived”.

On the face of it, it looks to me like a case of regurgitated raisins.

Update: Left-wing demonstrations prevent the conference from going ahead.

Brandeis University’s Jytte Klausen, in her book “The Islamic Challenge,” provided the perfect example of this quandary. A German court ruled in 1995 that while Jews could be exempted from the strict laws governing animal slaughter, Muslims could not.

The rules governing Kosher slaughter and Muslim customs are similar. The Jewish authorities, when consulted by the court, were adamant that their religion absolutely required ritual slaughter. When it came to the Muslims, however, the court consulted Islamic authorities in Cairo, who told them that, in an emergency, Muslims could do without ritual slaughter.

Muslims in Germany were furious. “We are not lost in the desert, there is no emergency here,” a German Muslim told me as he gestured at the well-stocked Berlin cafÈ in which we were sitting. “If Jews can be allowed their religious customs, why not us?”