BALTIMORE, 1963. TUBBY housewife Edna Turnblad, polyester frock stretched taut over her body (picture Ralph Kramden in drag), tries to explain to her husband Wilbur why their daughter Tracy (picture a teen-age Ralph Kramden in drag) likes to do the mash potato on the local TV dance show.

"Wilbur," she says, "it's the times. They are a-changin'. Somethin's blowin' in the wind. Fetch me my diet pills, would you Hon?"

It's just a taste -- or whiff -- of John Waters' hilarious trash blanche comedy "Hairspray," the latest from the guy who gave us cult hits "Pink Flamingos," "Mondo Trasho," "Desperate Living" and "Polyester."

Shot in Waters' hometown, with cult faves (renowned transvestite Divine as Edna, blond-on-blond regular Mink Stole) and kitsch-mongering household names (Sonny Bono, Pia Zadora, ex-Blondie Debbie Harry), "Hairspray" is a gleeful wallow in the 1960s gook of beehive 'dos and Leslie Gore music -- with a positive desegregation message besides.

White teen-agers do the Madison, the Pony and the Roach to black music on "The Corny Collins Show" while their black contemporaries watch from home: Their onscreen dancing is restricted to "Negro Day," the last Thursday of the month.

The issue divides Waters' crazy-quilt world. Schoolgirl Tracy (Ricki Lake) leads the positive integrationists, with fast-talkin' black deejay Motormouth Maybell (Ruth Brown). The opposition's led by TV station chief Arvin Hodgepile (Divine, in men's clothing) and the blond 'n' weaselly Von Tussle family -- Tracy's personal rival Amber (Colleen Fitzpatrick) and parents Velma (Debbie Harry, with Connie-Stevens-Meets-Mommie-Dearest relish) and Franklin (Bono at his all-time nasal best).

Waters writes warmth into his caricatures, lifting "Hairspray" above cartoon cult. You love 'em all, whether it's Divine squeezed into a tight, groovy little number she picked off the rack at the "Hefty Hideaway" shop, or Zadora's Beatnik, who thinks she is Odetta, or the demented Dr. Frederickson (Waters himself), a psychoanalyst who assails Tracy with a psychedelic pinwheel and a sort of fluorescent electric cattle prod for teens. It seems inappropriate to call ick noir auteur Waters a breath of fresh air. But, amid the stale odor of our man-made, musty, Muzaked lives, he's a welcome gust of Renuzit.

HAIRSPRAY (R) -- Area theaters.