Last week, to no one's real surprise, the Motion Picture Association of America ratings board slapped the sex-addiction drama 'Shame' with an NC-17 rating. The surprise is that distributor Fox Searchlight is not only not contesting the ruling, but embracing it: as the studio insisted to The Hollywood Reporter, the NC-17 rating should be "a badge of honor, not a scarlet letter." If only. Pretending that NC-17 no longer carries a stigma that severely limits box-office potential won't make it so. Critics and discerning moviegoers have been complaining for more than 20 years that we need a new adult rating that distinguishes between pornography and serious dramas -- like the Oscar-hopeful 'Shame' -- that are not for kids. In fact, we should go beyond that. We need a rating that doesn't just protect kids from adult content, but one that protects adults from cinema oriented toward the juvenile.