Mehran Karimi Nasseri takes the 610.13 francs from Dr Philippe Bargain, the airport's chief medical officer, and puts the money in his pocket without counting it. Mr Nasseri's response to the gift - a subdued "very good" - is about as emotional as the man who has lived for the past 11 years on a red bench in the pre-departure lounge of terminal 1 at Roissy Charles de Gaulle Airport ever gets.
Airport staff and air crews call him Alfred or Sir Alfred, and have made them their informal mascot. "He is very even-keeled," Dr Bargain says of his 56-year-old patient. "He doesn't get enthusiastic."
Yet, there is something touching about Alfred, with his sad, Charlie Chaplin eyes and smile. Someone in the US just read an article about him and was moved to send an anonymous money order for $100 to Dr Bargain.
"Please let Mr Nasseri know that many people are concerned for his well being, and that we feel bad about his plight," the letter says. "Please let him know that we are hopeful that he will have a safe, comfortable and happy future. Sincerely yours, A Concerned American Citizen."
The article in question portrayed Mr Nasseri as the hapless victim of Kafkaesque bureaucracy, alluding only once to his "mental confusion".
Dr Bargain refuses to see Alfred as a symbol of 20th-century man. "It was his choice," he insists. "The French social services would have taken care of him but he refused. Alfred's nice but he's a pain - with his Marks & Spencer toothpaste, his arrogance, his detachment. He wants you to know he's not just anybody."
The trickle of sympathy cheques for Alfred have turned Dr Bargain into his de facto banker. Without an address, Mr Nasseri cannot have a bank account, so the doctor deposits the cheques and gives him cash, which he uses to eat at the airport McDonald's. On the bottom of the American's letter, Mr Nasseri writes in the same, erratic scrawl in which he keeps his diary, "Received from Dr Bargain . . . Sir Alfred Mehran".
"I was in Heathrow in 1981," Mr Nasseri - Alfred - explains. "I was given a paper by the inspector and it said, `Sir Alfred Mehran'. It was just before the wedding of Charles and Diana - that's why they gave me the title."
Dr Bargain is moving from affection to exasperation. "I haven't heard that one before," he says. "You're crazy, Alfred, you're really crazy." Sir Alfred doesn't respond. Little of his past is certain. The refugee papers he received in Belgium in 1981, which he lost in 1988 and which were finally restored to him in July 1999, establish only his name, and that he was born in the Iranian town of Masjed Soleyman in 1943.
From his own, ever-changing account, pieced together by Dr Bargain and his volunteer lawyer, Mr Christian Bourguet, it seems that his father was a medical doctor working for the Anglo-Iranian Oil Company, his mother an unwed British nurse. He has at times claimed she was a Scottish aristocrat. "Here at the airport, we say he's the secret child of the queen of England," Dr Bargain jokes.
Alfred has alluded only in passing to the mysteries that broke his life: his Iranian family's rejection of him, mistreatment by the shah's secret police. He claims to have earned a bachelor's degree in psychology, speaks English and Farsi, has picked up French and has the cultural vocabulary of a university graduate.
Dr Bargain believes he may have fled Iran to avoid conscription in the 1980-1988 Iran-Iraq war. Despite the media coverage given to Alfred's case, no doctor or relative has ever come forward to explain what happened. Despite Dr Bargain's appeals to humanitarian and refugee aid organisations, no one has offered to give Alfred a home.
Alfred's stay in France began in August 1988, when he was sent back from Heathrow Airport because he had no identity papers. The French jailed him for four months, then freed him in Roissy, where he has stayed ever since.
Three months ago, the Belgian government finally agreed to send Alfred's lost refugee papers through the post. Under the Schengen agreement, the French authorities gave him a residence permit and international travel card in September. "We held a little celebration with the lawyer," Dr Bargain says, "but Alfred wasn't happy. He said he thought the papers were fake. The lawyer, who had spent 10 years trying to help him, nearly choked."
Now that Alfred is free to travel, Dr Bargain tells him every day that he must leave Roissy airport, but he keeps finding excuses to stay with the vinyl bench and luggage trolley holding 11 years accretion of books and papers.
In the meantime, he complains about the commotion in the terminal, which keeps him awake from 7 a.m. until midnight. He shaves and showers every morning in the airport's public bathroom, and lives on hand-outs.
So why has Roissy become the place he is too frightened to leave? "I have a British Airways ticket," he tells me, referring to the 1988 flight he was forced to reverse. British Airways flies from here. I want to go to London."
But you can go to London," Dr Bargain answers, sighing. "It's like a ping-pong game with Alfred."
An airline station manager walks by. "Hi Alfred. You still here? I thought you were going."
"Later, later," Alfred murmurs.