sentences:  Dolby Digital Surround EX has since been used for the "Star Wars" prequels on the DVD versions and also the remastered original "Star Wars" trilogy.A number of DVDs have a Dolby Digital Surround EX audio option.The cinema version of "Dolby Digital EX" was introduced in 1999, when Dolby and Skywalker Sound, a division of Lucasfilm Ltd., codeveloped "Dolby Digital Surround EX"™ for the release of "".