While heated negotiations between the ''Simpsons'' voice cast and their home studio seem to be a near-annual event, this latest pact is a four-year agreement that will earn the actors nearly $400,000 per episode.

According to the industry trade papers, the voices are back to work doing readings for the show's 20th season.

The 20th season is expected to only include 20 rather than the usual 22 episodes, but this latest set of negotiations could hardly be considered acrimonious. Talks in 2004 delayed the start of the following ''Simpsons'' season and it has been rumored that the 1998 impasse was so tense the studio contemplated hiring alternative vocal stars.

Dan Castellaneta (Homer), Julie Kavner (Marge), Nancy Cartwright (Bart), Yeardley Smith (Lisa), Hank Azaria (Moe) and Harry Shearer (Mr. Burns) are all signed on.