The Los Angeles edition of the All Tomorrow's Parties (ATP) festival, originally set for June 20-22, has been postponed until the fall. A spokesperson says ticket sales had been "sluggish" for the alternative music festival, which is being curated by "The Simpsons" creator Matt Groening. The event has been rescheduled for Sept. 26-28.

More than 30 acts, including Patti Smith, Nick Cave, ...And You Will Know Us By The Trail Of Dead, Mission Of Burma, the Breeders, Yo La Tengo, Wire, and the Magic Band, had been booked for ATP, with shows running concurrently at Hollywood venues the Palladium, the Palace, and the Henry Fonda Theater. Organizers hope to utilize the same halls and present some of the same acts in September.

No word was available on the status East Coast edition of the fest, which was to be held in September in Asbury Park, N.J., but will instead be moved to a "new location," according to the ATP Web site. Stephen Malkmus is still expected to curate.

ATP had its start in the U.K., and this is the second year that festivals have been scheduled in the U.S. Last year, Sonic Youth curated a four-day event at the University of California at Los Angeles, which saw performances from Wilco, Pearl Jam's Eddie Vedder, Television, Big Star, Aphex Twin, Stereolab, and Sleater-Kinney, among others.

As previously reported, the festival's label arm, ATP Recordings, is branching out with individual releases by the Magic Band and Bardo Pond. Both albums are due in August, and will be distributed by Touch & Go.