When Hortense, the maid, dialed the phone to begin "The Boy Friend," the University of Maryland musical was off to a bum start. In the '20s girls' finishing schools on the Riviera, let alone most any other place, didn't have dial phones. Ah, the time we've wasted since, watching players dial phones.

Anachronisms are the traps in Sandy Wilson's beguiling '50s musical about the '20s. While we now are almost as far from Wilson's '53 London creation as it was from his '26 story period accuracy is vital in this enchanting valentine to innocence.

Thus, while Ron O'Leary's production is a pleasant enough campus entertainment, it's not in the same league with such remembered College Park achievements as last year's "Macbeth" or "Camino Real" a few semesters earlier!

Basically, "The Boy Friend," a miniature in amber, is not a sensible choice for long, narrow, accoustically dead Tawes Theater. To fill in the stage spaces, O'Leary has more than doubled the number of Madame Dubonnet's students, giving them such non-'20s names as Billy, Candy and Ginger. With a mask only for Tony (the Hon. Anthony Brockhurst disguised as a messenger boy), the point of the masked ball is wholly lost.

D. Stephen Paver's notion of a plerette costume suggests that his research was in Minsky, not Laver, and what on earth is Lady Brockhurst wearing? Generally the hair styles, especially for Polly and some of the boys, are more '70s and '20s.

Nor does it help to troop on the chorus as background for duets. Why are those gorgeous showgirls inching down a staircase during the Pepe-Lilita tango? To divert us from not-much-of-a-tango? Why has no one instructed a French girl how to pronounce "les hommes?"

One expects accuracy from a major theater department. The essence of "The Boy Friend" is its utter seriousness, Julie Andrews, Millicent Martin Dilys Lay, Moyne MacGill (Angela Lansbury's real-life mother) and Eric Berry (recently here as Charlemange in "Pippin") put over Vida Hope's original staging because they never ever, poked fun.

"The Boy Friend" itself remains charming, and albeit muffled, Gregg Tallman's Bearcats aren't bad. Though the audience applauded even the drop curtain, it is depressing that a university theater, which should know the point, does not.

After performances tonight at 8 and Sunday at 2, the run resumes Thursday.