The trial for state Sen. Vince Fumo and three co-defendants likely won't start before early next year, prosecutors and defense lawyers said at a federal court hearing yesterday.

U.S. Senior District Judge William H. Yohn Jr. did not set a trial date.

Prosecutors also said Fumo's trial could last three to four months. They plan to call at least 100 witnesses to testify for the government.

Defense attorneys said they couldn't reliably estimate how long a trial might take until they see what evidence the feds have.

The feds hit Fumo, 63, with a 139-count, 267-page indictment on Feb. 6 charging him with conspiracy, fraud, obstruction and tax felonies.

Also indicted were Ruth Arnao, 50, a former top aide to Fumo, and two ex-computer aides of Fumo. Arnao was charged with conspiracy, fraud and obstruction, and with filing a false tax return.

Earlier yesterday, the two ex-computer aides for Fumo, Leonard Luchko, 50, and Mark Eister, 37, were arraigned before U.S. Magistrate L. Felipe Restrepo on conspiracy and obstruction charges. They pleaded not guilty.

Luchko and Eister had been indicted on obstruction counts in June but were charged anew when Fumo and Arnao were charged in a superseding indictment.

Fumo and Arnao pleaded not guilty to all charges on Feb. 7.

All defendants are free on $100,000 bail, and their freedom to travel has been restricted.

During yesterday's hearing before Yohn, prosecutors agreed to turn over all their discovery in the case to defense attorneys within 45 days.

The feds have plenty to hand over: At least 100,000 documents, including e-mails, grand-jury transcripts, summaries of FBI interviews with witnesses, bills, bank-account statements and store receipts.

Prosecutors declined to say whether any of the discovery included wiretaps or video surveillance.

Defense attorneys asked Yohn for 45 days to review the discovery materials once all have been received.

Then Yohn is expected to hold another hearing, probably in late spring, when he may set dates by which all pretrial motions need to be filed and also set a trial start date.

In the meantime, both sides appear ready to rumble.

Prosecutors said they plan to file court papers soon asking Yohn to hold a hearing to determine whether lawyers for Fumo and Arnao should be disqualified because of potential conflicts of interest.

Fumo is being represented by the firm of Sprague & Sprague, and Arnao is being represented by Edwin J. Jacobs Jr., William H. Lamb and Joel L. Frank.

Yohn, directing a question to Sprague, said he understood Sprague might be filing court papers alleging prosecutorial misconduct.

Sprague said he wasn't in a position to comment on that yesterday.

One other thing left unresolved yesterday is whether the trial would be conducted four days a week or five days.

Sprague, 81, said courtroom proceedings move along more "efficiently" if lawyers and the jury have Fridays off.

Yohn said he preferred five days a week, 9 to 5, but would defer a decision. *