The Shostakovich centenary and the 250th anniversary of Mozart's birth are linked in the Philadelphia Orchestra's 2006-07 programming, with humor as a common theme. "Humor has many sides," said Eschenbach when the season was announced earlier this year. "Mozart's musical wit is cheerful and precocious, while Shostakovich's humor is dark and cynical."

In addition to the Fifth Symphony (which remains on tap, alongside other works, through October 3), the Fabulous Philadelphians and Andr_ Watts perform Shostakovich's Piano Concertos Nos. 1 and 2 on October 12-14. And for more Mozart this fall, from November 30 to December 3, Eschenbach will serve as both conductor and pianist in the composer's Piano Concertos Nos. 12 and 23.

Other highlights of the season include new works by Henri Dutilleux and John Harbison as well as the continuation of the orchestra's five-year survey of Mahler's complete symphonies and song cycles. Eschenbach conducts the Symphony No. 4 (with soprano Marisol Montalvo) November 16-28 and the Symphony No. 2 ("Resurrection") May 3-5. The cycle began in the 2003-04 season.

Former music director Riccardo Muti returns to conduct the orchestra in Schubert, Hindemith and Strauss November 2-4. Valery Gergiev leads the ensemble in Debussy and Schubert February 8-11. Other guest conductors this season include Rafael Fr‹hbeck de Burgos, Charles Dutoit, Marin Alsop and Peter Oundjian.

Returning guest soloists during the season include violinist Nadja Salerno-Sonnenberg and pianists Martha Argerich and Yefim Bronfman. Making their Philadelphia Orchestra debuts will be violinists Baiba Skride and Janine Jansen and pianists Lars Vogt and Piotr Anderszewski.

For more information on the Philadelphia Orchestra's 2006-07 seasons at Verizon Hall and at Carnegie Hall in New York City, visit www.philorch.org.