The boys of the Alamo have received a stay of execution. Scheduled to die en masse this Dec. 25, Davy Crockett (Billy Bob Thornton) and Co. won't bloody the Texas soil until April 2004. According to Disney, that's how long it will take director John Lee Hancock to finish his Lone Star epic ''The Alamo,'' which was to be the studio's Christmas-season box office siege. ''Post-production on an epic ensemble piece takes time, and no deadline, no prestige release date, no awards season is worth more to me than the movie being fantastic,'' says Hancock in a press release from Disney. It's an odd note for Disney to strike at the end of a year that's seen the success of ''Finding Nemo'' and ''Pirates of the Caribbean,'' and it leaves the studio without a year-end Best Picture contender. But with all the extra time, maybe they could give the movie a happier ending.