Mozart's "The Magic Flute" is the most wonderful of operas -- in the literal sense: full of wonders. It is also the most problematic for sensibilities of the late 20th century, full of random remarks about women and racial/color references focused on the secondary character of Monostatos, a Moor. These have always been disturbing to people who looked past the great tunes and studied the libretto; in the age of the surtitle, they have become obvious to the most casual patron.

In the Wolf Trap Opera Company's outstanding production, which opened last night at the Filene Center and will have its final performance tomorrow night, the wonder comes across intact and enhanced, while the problems have been almost eliminated. "The Magic Flute" still looks like an opera about an initiation into a patriarchal secret society -- which, on one level, it is -- and a line or two about women talking too much manages to find its way into the surtitles. But if you consult the original text, you will see what a monumental cleanup has been quietly done.

There has been some slight censorship and tampering with the text of a masterpiece. And I am all for it. Pristine texts should be kept for scholars, but it is hardly possible for comic art to survive as such and keep a mass audience for two centuries without minor adjustments to changing popular tastes and conditions. Ethnic humor that was truly funny in the Vienna of 1791 can be offensive in the Washington of 1990, and Mozart and his librettist-entrepreneur-baritone Schikaneder, their eyes firmly fixed on the box office, would have been the first to change the text in nonessentials to follow changing popular tastes.

"The Magic Flute," unlike many comic works of similar vintage, deserves the effort involved in such adaptation. It contains (in the role of Papageno the bird-catcher) some of Mozart's funniest and most popular music, the roots of the 19th-century Viennese operetta style. It also has (in the Queen of the Night's two arias) some of the most breathtaking music he ever wrote for the soprano voice; in the arias of the tenor Tamino and the soprano Pamina, some of his most appealing romantic music -- again, looking far ahead into the 19th century; and in the music of Sarastro and his associates, some of the finest religious music ever written.

The Wolf Trap production meets all the music's requirements superbly and with a sense of ease. Tamino's music requires a lightness of tone and grace of movement that also must allow for intensity of expression, and Gregory Cross supplied those qualities superbly. The role that requires the most acting skill is that of Papageno, and Mark Oswald has that in abundance, as well as a voice exactly right for the music. Kelly Anderson's Sarastro has nobility and exemplary vocal control; a little more weight would be welcome in the lower register, and time should provide that.

The two best voices in a production that had no weak points were Laura Lamport, who has exactly the right bright, agile and precise upper register for the Queen of the Night, and Janet Williams, who sang the role of Pamina with a purity of tone, ease of production and emotional communication that make one want to hear much more of her work.

Any of the three ladies-in-waiting, Carolyn James, Phyllis Pancella and Tichina Vaughn, could have taken a much larger role had one been available. They worked together with a fine sense of musical and theatrical ensemble and wit, for which stage director Julian Hope deserves considerable credit. Conductor Steven Sloane styled the music expertly, and the orchestra and chorus were fine.

The costume and set designs of David Hockney are skilled, provocative and imaginative, particularly in the curious animals who come out to hear Tamino's flute. With Zack Brown on the job, the Washington Opera has a fair chance to match or surpass this element in its new "Magic Flute" for the coming season, but it will be interesting to see whether it can come close in the pure quality of the singing.