Konrad Kujau's fingers are itching again.
The ink on the treaty uniting the two Germanys was barely dry before he had forged a copy and put it up for sale.
It hangs in his cramped "Gallery of Fakes" along with dozens of paintings bearing the signatures of Dali, Monet, Miro, Rembrandt and other artists.
Seven years after going to prison for his role in history's biggest literary swindle, the man who wrote the so-called secret diaries of Adolf Hitler has become so renowned for his bogus autographs and artwork that other forgers now forge his forgeries.
"I make my living as a forger," the 52-year-old artist cheerfully admitted while doodling Napoleon's signature on a pad already full of ramblings in Bismarck's hand.
These days, however, Kujau is careful to issue certificates of unauthenticity with his work, and stamp the fakes with his own name just to be sure.
Released after serving three years of his 4 1/2-year sentence, Kujau still insists he never intended to pass off the 63 volumes of Hitler memoirs as the real thing.
The diaries, he said, were commissioned by Gerd Heidemann, a star reporter for the weekly newsmagazine Stern, which paid a record 9.3 million marks (then $3.1 million) for them and began publishing excerpts in April, 1983, touting it as the scoop of the century.
The swindle also took in Newsweek magazine and the respected London Sunday Times, which had bought publication rights.
Within days, federal investigators and historians revealed the handwritten diaries as crude fakes plump with historical inaccuracies.
The ridicule still stings Kujau, who said he spent more than two years painstakingly penning the diaries.
"I researched over 590 books and more than a thousand newspaper articles," Kujau said a bit defensively. "Some prominent historians were convinced the diaries were genuine."
Kujau and Heidemann were quickly arrested, and their various alibis, theories and exploits became favorite fodder for sensationalist tabloids.
Heidemann, it turned out, was so obsessed with the Nazi era that he once sold his family's home to buy a yacht that belonged to Hitler aide and Luftwaffe chief Hermann Goering.
Investigators found about half the diary payment hidden aboard the boat, which Heidemann kept docked near his Hamburg home.
Kujau, who merrily forged Hitler autographs for spectators at his trial, had been an unknown artist and dealer in military memorabilia before meeting Heidemann.
"He sat in my living room in January, 1981, and waited for my friend Edith to go to bed before he told me he wanted to buy Hitler's diaries," Kujau recalled.
Heidemann later insisted Kujau had convinced him the diaries were recovered from the rubble of a small plane that crashed into a barn in eastern Germany during the last days of World War II.
Kujau said the story was the product of Heidemann's imagination, not his own.
"How could he have not known they were fake when I was sending him letters and even a birthday card in Hitler's handwriting?" Kujau demands.
Each man blamed the other for perpetrating the massive fraud, and both went to prison for the crime.
Stern never did find about $1 million of the money paid, leading Kujau to speculate even today that another person was somehow involved.
Although the scandal made the shadowy little memorabilia dealer from Stuttgart famous, Kujau becomes angry when he considers the price he feels he has paid.
"No way was it worth it," he said.
"I lost three years of my life and developed cancer of the larynx in prison," he rasped in a voice he thought he had lost forever two years ago.
"I've undergone surgery six or seven times, and I had to learn to speak all over again," he recounted. "I couldn't utter a word, not a single word, for seven months."
The 1.6 million marks (then $500,000) Kujau earned for the diaries was quickly swallowed up by taxes, fines and lawyer fees that left him deeply in debt.
He now fetches anywhere from 600 marks (about $400) to 60,000 marks ($40,000) for his fake masterpieces, and is often called upon to authenticate work or appear on TV shows to discuss art fraud.
"I can tell a fake in a minute," he said, revealing that he instantly ages his own masterpieces by baking them in an oven for a few hours. His year-old gallery now houses 110 works, with another 90 on exhibit in Hamburg.
"I don't copy known masterpieces," he said. "I do original work in the style of the masters. I study their brush strokes and read about their lives. I use old colors and old wood for the frames."
And the challenging question always lingers in his mind:
"How can I fake out the experts?"
Art dealers and lawyers sometimes contact Kujau to make sure he didn't forge a work being sold as an original, or to make sure he did forge a copy.
"I hear that someone is out there selling fake Kujau fakes," he bragged. "They've turned up in the United States and France.
"It doesn't really bother me," he added.
And the unsavory past has not exactly made Kujau swear off the "d" word, either.
"A couple of publishers have approached me about forging the satirical diaries of Erich Honecker," he said, dashing off a convincing replica of the ousted East German Communist leader's signature.
He surveyed his work with a satisfied grin and a smug boast.
"I do believe that even Erich would now say he had signed that himself."