Also slated to appear at the April 13 event at the Beacon Theatre in Manhattan are Will Arnett, Matthew Broderick, Steve Carell, Stephen Colbert, Susie Essman, Will Ferrell, Tina Fey, Jonah Hill and Kevin James.

Conan O'Brien, Rosie O'Donnell, Amy Poehler, Adam Sandler, Sarah Silverman and Triumph The Insult Comic Dog are included on the lineup, as well, Comedy Central announced Monday.

Jon Stewart will serve as host of the evening, which will be filled with live performances, sketches and short films from a roster of comedy all-stars.

The event was planned to raise money "to help ease the severe shortage of effective schools and education programs for autistic children and adults," organizers said.

Starting April 15, the show will be available for download on iTunes and xBox Live Marketplace for 30 days.

All proceeds from the $1.99 download will go directly to the charity.

In addition, comedycentral.com will stream the entire broadcast online April 14.

The October 2006 edition of the star-studded show raised more than $2.5 million, Comedy Central said.