Lawyer Edward Greenspan has resigned his seat on the board of directors of Cryptologic Inc. because he is too busy defending his client Conrad Black, the company said Monday.

The developer of internet gaming software said Greenspan's workload, particularly as the defence lawyer in the Hollinger International case, "no longer permits him to devote the time and attention to serve fully as a director of CryptoLogic."

Black is scheduled to go on trial in Chicago next March on racketeering and fraud charges related to his operation of the media company Hollinger International Inc. He was also recently charged with tax evasion.

Black has pleaded not guilty to those charges.

In court documents filed Friday, Black argued that the charges against him should be dropped, the Toronto Star reported.

In the filing, Black called the laws under which he has been charged vague and not properly defined.

Black also argued that prosecutors have prejudiced the case because they have drawn attention to his wealth.

He called those references "irrelevant," "inflammatory and prejudicial."

"Since Biblical times, and probably before, the wealthy have been envied and condemned," he said in the filing.

"It is easier for a camel to pass through the eye of a needle than for a rich man to enter the kingdom of God," Black said, quoting Matthew 19:24.