Tour de France winner Floyd Landis’s efforts to clear his name got a small boost Wednesday when officials at France’s national anti-doping laboratory admitted making an “insignificant” numbering error on a urine sample that later tested positive for testosterone.

However the director of the IOC-accredited laboratory at Châtenay-Malabry said the "typing error" had no bearing on the finding of unusual testosterone/epitestosterone ratios in both A and B samples taken after Landis's epic victory in Stage 17 of the Tour.

Since learning of the positive test Landis has consistently maintained his innocence in the affair and is basing his defense ahead of an anticipated ban from the sport on what he believes are errors on the part of the French lab.

On Wednesday the laboratory conceded that a labeling error had been made.

The French newspaper Le Monde reported Wednesday that the B sample had "ill-advisedly been indexed with the wrong number on the accompanying report."

"The identification number of Floyd Landis was 995 474 while on the report it was listed as 994 474. That doesn't signify that the B sample did not belong to the American. But it will be seized upon by his lawyers who will try to bring new elements to his (defense) case at a presentation on Friday."

Landis and attorney Howard Jacobs have raised the numbering issue in the past but laboratory director Jacques de Ceaurriz had not commented on the discrepancy until now.

"It's an error as regards numbering, a typing error which has no significance whatsoever on the findings in the samples," said de Ceaurriz, adding that the World Anti Doping Agency (WADA) was aware of the incident. "These little mistakes happen. They are corrected, and noted."

"It wouldn't surprise me that Landis's lawyers use this information,” De Ceaurriz added, “but the error does not wipe out the result of the analysis."

On Tuesday an inquiry was launched after hackers pirated the computer system at the French laboratory.

De Ceaurriz confirmed to AFP that an investigation was under way after the discovery that the lab's computer system had been accessed from outside.

"An inquiry is under way. I'm not making any comment because the incident is probably linked to affairs currently being handled by the laboratory," de Ceaurriz told AFP. "We have been aware of this for some time and in the past week our suspicions have been confirmed."

According to French sports daily L’Equipe, police have identified an alleged suspect based on e-mails and letters sent by the individual, who is reported to be close to Landis, in which he cited internal documents to condemn testing errors by the laboratory.