PARIS, Oct. 5 (Xinhua) -- Very few people can afford 4.9 billion euros (6.7 billion U.S. dollars), not to mention a computer consultant with a monthly pay of 3,168 dollars.

Jerome Kerviel, 33, however, had to pay the great amount of money due to his fraud performance which had left an irreversible loophole and brought Societe Generale (SocGen), one of the biggest European bank, to the brim of bankruptcy.

Kerviel's lawyer Olivier Metzer said Tuesday they would appeal against the court's conviction to sentence Kerviel to five years in prison and to compensate the 6.7 billion dollars including interest to SocGen.

"We are going to eject an appeal against the unacceptable judgment," Metzner told reporters.

It was irrational for the ruling to exclude the bank system from any responsibility and only blame all damage on the individual defendant, Metzer argued.

Paris criminal court convicted the former trader guilty of breach of trust, forgery and entering false data into computers.

Kerviel admitted his sneaking performance but insisted his supervisors knew what he was doing and neglected him until the amount turned too big to hide.

A judge at the court declared that the defendant's testimony of SocGen's awareness of his activities could not be verified.

Between late 2007 and early 2008, Kerviel gambled position with fictive transactions up to 50 billion euros (68.9 billion dollars) and finally caused the sky-high loss.

Local media estimated it would cost Kerviel 17,000 years to reimburse the damages to SocGen.