"Happy Birthday, Gemini," a sluggish, sappy hodgepodge of domestic and generational farce, resolved by inspirational speeches of truly merciless banality, sustains the curious modern movie convention of portraying Harvard undergraduates as stuperying stupes. From "Love Story" a decade ago to "A Small Circle of Friends" a few weeks ago to "Gemini" at the unlucky theater of your choice today, one could trace and unbroken line of Harvard asininity. Is Hollywood trying to Make a Statement? Maybe it's part of a cunning conspiracyto discourage applications.

Derived from an apparently scatterbrained play, called simply "Gemini," by Albert Innaurato, "Happy Birthday, Gemini" seems to have been ponderously "opened up" by director Richard Benner, showing for less resourcefulness than he did on "Outrageous." The contrived and then undeveloped comic turmoil is supposed to be caused by the surprise visit of Judith and Randy Hastings, a WASPy set of siblings, played by Sarah Holcomb and David Marshall Grant, to theSouth Philadelphia home of schoolmate Francis Geminiani, played by Alan Rosenberg.

For 10 to 15 minutes one feels pleasantly mislead. The author seems to have a promising subject in his sights, and he introduces a number of characters with funny downbeats. When Francis looks chagrined at the unexpected arrival of his college friends, the cause appears to be a guilty surge of social panic. College snob that he's evidently become, Francis acts embarrassed at the prospect of his well-heeled, refined chums meeting his loved ones, who happen to be hearty, demonstrative, generous vulgarians.

Th chief vulgarian is his doting bachelor papa, a swarthy, genial butcher played by Robert Viharo, recently seen as the small-time hood who married James Cann's ex-wife in "Hide in Plain Sight." Father seems to have been abandoned by the boy's haughty society mother years earlier; indeed, one is left with the peculiar impression that Father Geminiani probably gave birth to little Francis. At any rate, dad plans a 21st birthday party for his college boy, who's a day short of this milestone when the story begins.

Joining dad in the celebration are such well-wishers as his compulsively ladylike mistress, Lucille, played by Rita Moreno, and the progressively grotesque comic relief next door: Madeline Kahn as a raucous, slatternly waitress named Bunny and fatso Timothy Jenkins as her ridiculous-pathetic son, a childish, adolescent blimp named Herschel.

The idea of someone like Francis feeling ashamed of his family when confronted with associates from a tonier social class would seem to be a perfectly sound premise for a play. Although "Gemini" starts with this idea, neither Innaurato nor Benner seems prepared to take it anywhere revealing.

What's the point of having Francis invent monstrous lies to try to scare his friends away -- he tells them that his father is a Mafia assassin for starters -- unless the lie grows out of a shameful sense of shame, which would presumably be discredited and overcome in the course of a fundamentally comic show?

Instead of dealing with the interesting theme that meets the eye, Innaurato neglects it in order to exploit what I suppose was considered a more topical and racy angle. Francis' real problem, it now appears, is homosexual panic. Judith, with whom he'd begun an affair at school, is eager to get cozier, but Francis suspects that the Hastings he truly longs to sleep with is brother Randy. When he confesses his confusion, Judith gets nastyand Randy is appalled, although he challenges Francis to act on his impulses at one impulsive juncture, inviting the audience to entertain lewd possibilities before backing down.

After dragging in the sex motive with scant justification, Innaurato seems to discard it too after some idle, contrived dramaturgical diddling. A formidable fumbler, Innaurato can't seem to get a steady grip on any thematic handle. He just keeps groping for fresh, contradictory handles. At once pretentious and hopelessly disorganized (like his dreary young hero, it would appear), Innautato tends to compose scenes that evoke other playwrights or screenwriters without synthesizing into an original, coherent play he might honestly call his own.

There'll be a hollow echo of Tennessee Williams followed by Paddy Chayefsky followed by Edward Albee followed by Carson McCullers followed by Neil Simon followed by Herb Gardner followed by Matt Crowley followed by Sylvester Stallone, etc., etc., etc. It's workshop playwrighting, a collection of scenes from a disheveled work in progress that has somehow been mistaken for a presentable, finished creation.

The ostensible romantic triangle has a lot of trouble taking shape because the young characters themselves seem peculiarly distorted and unattractive. One never feels as if contemporary sex myths and adolescent confusion were forcing them into false positions and threatening their comradship. It always seems to be the author forcing things, and making a botch of his contrivances in the bargain.

Does it really matter whether Francis' predilections are, uh, different? Evidently not. The consoling speech, entrusted to his big understanding stud of a father, maintains that "the only thing that matters is you're man enough to find out ya gotta take a slug at the world, ya know."

Although Francis faces the world with renewed enthusiasm after absorbing this homely wisdom, one suspects that what he's probably looking for is not a manly mentor a lot like, well, dear old dad. Like Judy Garland in "The Wizard of Oz," he doesn't need to look much beyond his own back yard to find his heart's desire. Could Francis be an aberrant breakthrough -- the Daddy's Boy as ingenue?