Comingsoon.net is reporting that new voices have been added to the cast of the third Shrek movie, Shrek the Third.

Joining the cast for Shrek the Third is an all-new ensemble of actors and comedians. Grammy Award-winning singer/songwriter Justin Timberlake will play the role of Fiona's rebellious teenage cousin Artie, the inimitable Eric Idle (the "Monty Python" movies and series, "Spamalot" on Broadway) will play Merlin and John Krasinski (TV's The Office) will play Lancelot. Making up a new fighting force of fairy tale princesses are: Cheri Oteri (TV's Saturday Night Live) as Sleeping Beauty, Amy Poehler (the upcoming Blades of Glory, Mean Girls) as Snow White, Maya Rudolph (A Prairie Home Companion, TV's Saturday Night Live) as Rapunzel, and Amy Sedaris (Strangers With Candy) as Cinderella. Ian McShane (TV's Deadwood) will play Captain Hook.

Shrek the Third is scheduled for release on May 18, 2007.