Entertainment Weekly reports that LuPone will play the mother of Frank (Judah Friedlander), the wise-cracking writer on the hit series. An air date for LuPone's appearance has yet to be announced.

Tina Fey, writes, executive produces and stars as Liz Lemon in "30 Rock," "a workplace comedy where the workplace exists behind-the-scenes of a live variety show." The cast also features Alec Baldwin, Jack McBrayer, Jane Krakowski, Tracy Morgan, Keith Powell, Katrina Bowden and Scott Adsit.

For her performance as Rose in the recent revival of Gypsy at the St. James Theatre, Patti LuPone won the Tony Award, the Drama Desk Award, the Outer Critics Circle Award and the Drama League's Distinguished Performance Award. A Tony Award winner for her work in Evita, LuPone also earned an Olivier Award for her performances in the West End productions of Les Misérables and The Cradle Will Rock. Her other theatrical credits include Sunset Boulevard, Anything Goes, Oliver!, Working, The Old Neighborhood, Master Class and Pal Joey. LuPone also headlined two solo Broadway concerts, Patti LuPone On Broadway and Matters of the Heart, and received glowing notices for her performance as Mrs. Lovett in the Lincoln Center concert version of Stephen Sondheim's Sweeney Todd and a Tony nomination for her performance in the recent revival of that Sondheim work. She was seen in the Kennedy Center's staging of Marc Blitzstein's Regina and joined Audra McDonald for Los Angeles Opera's production of Kurt Weill and Bertolt Brecht's Rise and Fall of the City of Mahagonny. She was also seen as Rose in a Ravinia Festival concert run of Gypsy. Her screen and recording credits are numerous.

For more information about "30 Rock," visit www.nbc.com.