ONTD

Kirsten Dunst has checked herself into Cirque Lodge in Utah, Star has learned exclusively.

Spider-Man's Mary Jane made the decision to follow in the footsteps of Cirque patients such as Lindsay Lohan and Richie Sambora — after a week of wild parties at last month's Sundance Film Festival.  Fellow actress Eva Mendes is also in the mountaintop facility right now. Mary-Kate Olsen was treated at Cirque for food issues.

"She desperately needed help," a source in Utah tells Star. "She seemed to be intoxicated when she checked in because she was acting really erratic. She was extremely emotional, constantly breaking down in tears.

"She not in a good place right now, but thankfully, she's getting the help she needs."

Kirsten, 25, has long had a reputation for partying, with bloggers giving her the unfortunate nickname of Kirsten Drunkst.

ETA: This report conflicts with an item from the New York Post

February 1, 2008 -- KIRSTEN Dunst's strange ways have tongues wagging that she's "on the verge of a breakdown." The starlet came late, left early, and "acted erratic" during a recent event at Sundance, according to insiders. The source added that friends of the actress made apologies on her behalf, saying, "Kirsten is not in a good place right now." Dunst, who split from Razorlight rocker boyfriend Johnny Borell last year, has not been photographed or spotted out in recent weeks. A rep for Dunst told us, "Kirsten is fine."