Lohan's spokesman declined to give details of the episode involving the "Mean Girls" actress. But entertainment website TVLine.com said Lohan would play herself and serve as a celebrity judge when the "Glee" choir performs at a key contest toward the end of this current season.

The "Glee" guest stint marks a turnaround for Lohan, who was the butt of a joke on the show in 2010 when actress Gwyneth Paltrow's school teacher character Holly Holliday delivered a sharp quip about Lohan's many stints in rehab.

Lohan, 25, has been working hard to put her party girl past behind her and could have her probation formally lifted later this week after being in and out of court, rehab and jail since a drunk driving and cocaine possession arrest in 2007.

She hosted an episode of satirical TV show "Saturday Night Live" in February, and has landed the part of screen legend Elizabeth Taylor in an upcoming TV movie.

Actress Whoopi Goldberg also was reported on Tuesday to be appearing on "Glee" when it returns to the Fox network in April. TVLine.com said the "Sister Act" star would play a drama academy professor who auditions characters Rachel (Lea Michele) and Kurt (Chris Colfer) for a place at a performing arts college.

"Glee" returns to TV screens on April 10 and the third season's finale is scheduled for May 22.

(Reporting By Jill Serjeant; Editing by Bob Tourtellotte)

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