SNEAKERS should really be classed with films like THE ADDAMS FAMILY and STAR TREK--THE MOTION PICTURE, as a full-length feature which grew out of a TV series. This anemic high-tech caper resembles nothing so much as an extended episode of "Mission: Impossible," sans Lalo Schifrin's infectious theme music. Robert Redford plays Martin Bishop, leader of a motley group of electronics wizards who make a living by breaking into institutions to test their security. His band of merry-men-with-shady-pasts includes Crease (Sidney Poitier), a former CIA agent; Mother (Dan Aykroyd), a man equally obsessed with gadgets and conspiracy theories; Carl (River Phoenix), a precocious computer hacker; and Whistler (David Strathairn), whose blindness has heightened his genius for audio technology. Bishop, it turns out, has a personal history even murkier (though more politically correct) than that of his colleagues. As a college student, he and fellow hacker Cosmo (Ben Kingsley) had arranged for electronic "donations" of funds from bodies like the Republican Party to organizations like the Black Panthers. Cosmo got caught and went to jail, while Bishop has stayed free--until now, when a Government agency wants him to carry out an undercover op in return for clearing his record. His mission--should he decide to accept it--is to steal a mysterious black box capable of breaking the codes to any security system in the US. SNEAKERS is fun when it concentrates on the high-tech gadgetry used by Bishop's team. Elsewhere it drags, mainly due to uninspired direction and sloppy writing; an abundance of acting talent, including Mary McDonnell as an old flame of Bishop's, is wasted on characters as thin as silicon chips. It's all passably entertaining, but there's precious little that will stay with you; like so many contemporary movies, this one self-destructs five seconds after you leave the theater.