A Los Angeles judge had some harsh words for Lindsay Lohan today: Don't screw up again or you'll end up in jail with no chance of bail. The troubled star was in court to answer a felony charge that she stole a pricey gold necklace from a jewelry store near her home.

Lohan meekly answered, "Yes sir," when asked if she understood the charge against her – grand theft of personal property totaling $2,500.

Then her attorney, Shawn Chapman Holley, pleaded not guilty on behalf of the starlet.

Lohan's string of problems stemming from dirty tests after a misdemeanor DUI conviction left the prosecutor in no mood for leniency. Deputy District Attorney Danette Meyers – who filed the previous case against Lohan -- asked the judge to violate her probation from that case.

Meyers struggled to get Lohan to serve serious jail time following several court hearings last year, but the most time she ever spent behind bars was two weeks.

This time, Superior Court Judge Keith Schwartrz imposed a $40,000 bail and then gave a stern warning.

"You are in a different situation now with a felony filed against you," he said. "If you violate the law, I will remand you and set no bail."