Warner Home Video has announced that it inadvertently omitted content from discs in several of its Superman DVD editions (which street this week, see 'Superman Ultimate Collectors Edition'), and that it will exchange the flawed discs for ones that include the missing content. 

The Superman III Deluxe Edition is missing bonus content, and disc one of Superman:  The Movie Four Disc Special Edition is missing the Dolby Digital 2.0 mix. 

The affected packages are Superman Ultimate Collectors Edition, which includes both discs; Superman:  The Movie Four Disc Special Edition, which has the missing mix; and the Christopher Reeve Superman Collection, which also has the missing audio mix.