NYP2002041602-NEW YORK, April 16 (UPI)-- Noted theatre tomposer Stephen Sondheim and actress Chita Rivera who starred in Sondheim's first stage musical West Side Story chat at the American Theatre Wing gala honoring Sondheim for his years of accomplishment in the medium of Musical Theatre in New York on April 15, 2002. ep/Ezio Petersen UPI