Three former executives of Computer Associates have pleaded guilty to criminal charges associated with improper accounting at the software company.

The former employees, including the company's former chief financial officer, pleaded guilty before a US District Court in New York.

The US Justice Department and Securities and Exchange Commission (SEC) had earlier filed charges against Ira Zar, the company's former CFO, as well as former vice presidents of finance David Rivard and David Kaplan.

The SEC, FBI and other agencies are investigating improper accounting at CA during its 2000 fiscal year. The SEC accuses CA of claiming revenue from contracts before they were finalised. It also alleged that Zar and Rivard signed at least one backdated contract and that Kaplan oversaw the preparation of CA's improper financial statements.

The former executives pleaded guilty to conspiracy to obstruct justice and conspiracy to commit securities fraud, according to a CA statement. All three left the company last year.

CA's audit committee is nearing the end of its own investigation into the accounting improprieties. According to the CA statement, lawyers for the company and for its audit committee have reported to government investigators that the three men falsely denied the existence of the "35-day month" accounting practice while being questioned by them. The accounting trick involved prematurely recognising revenue for a given quarter on the basis of license deals that were actually signed in a later quarter.

CA also announced it has fired Steven Woghin, its former general counsel, effective immediately.