A federal judge has postponed the sentencing of former WorldCom (search) chief Bernard Ebbers (search) for his part in the record-breaking $11 billion accounting fraud by one month, to July 13.

Judge Barbara Jones issued a new schedule allowing several more weeks for Ebbers and prosecutors to file sentencing-related papers and for Ebbers to file additional papers in support of his bid for a new trial.

The sentencing was originally set for June 13.

Ebbers, 63, was convicted in March of orchestrating the record $11 billion accounting fraud at WorldCom, which collapsed in bankruptcy in 2002 and has since re-emerged under the name MCI Inc.

He faces up to 85 years in prison on nine criminal counts — conspiracy, securities fraud and seven false filings with the Securities and Exchange Commission.

Federal prosecutors told Judge Jones in papers made public Tuesday that Ebbers' grounds for a new trial "essentially rehash arguments that the court has previously considered and rejected."

Among those defense arguments are that Jones should have ordered immunity to three former WorldCom executives who were reluctant to testify, and who the defense claimed could have helped prove Ebbers' innocence.

Prosecutors said it would be an "extraordinary remedy" for a court to order the government to grant immunity to witnesses, and was not warranted in Ebbers' case.

Lawyers for Ebbers also say they should have been allowed to argue to jurors that the way WorldCom counted its revenue complied with generally accepted accounting practices.

"Nothing about the evidence presented during the trial requires a new trial now," the prosecutors wrote.

Besides Ebbers, five other former WorldCom officials who pleaded guilty in the massive fraud are scheduled to be sentenced this summer. All five struck plea deals with the government, and four testified against Ebbers.