HAMBURG, Germany -- [Roger] Luetz, a former Hamburg restaurant owner, is the "surprise witness" who, it was announced here last week, is scheduled to testify next month in the retrial of accused Sept. 11 conspirator Mounir El Motassadeq.

But when the affable, 42-year-old Luetz takes the stand Oct. 26, his credibility, in addition to El Motassadeq's fate, will be on trial.

The scenario Luetz paints, of a celebratory group of hijack plotters openly discussing flying lessons in the U.S. and trips to Afghanistan over chips and dips at his Mexican cafe, suggests much less operational acumen than the hijackers have been given credit for...

Efforts to convict the two most likely suspects from Atta's inner circle so far have run aground. One trial ended in an acquittal, and a guilty verdict for El Motassadeq was overturned on appeal...

In the three years since Sept. 11, 2001, Luetz has changed some details of the story he originally told police, which itself contained a few contradictions.

While admitting to some embroidery, Luetz insists the main points of his story were and still are correct, including the presence of Atta and El Motassadeq at a four-hour dinner party at Tacos y Tapas, the seedy eatery Luetz used to own on the edge of Hamburg's red-light district.
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