Thanks goes to Opera Theater director Jonathan Eaton for bringing Kurt Weill's "Lost in the Stars" to Pittsburgh. Thanks, too, for his mission to include a work each year that has special meaning for the African-American community. Weill's last Broadway musical, premiered in 1949, is a flawed masterpiece worthy of revival -- the more so because the production playing this weekend in the Byham Theater is of such high quality. Bringing in star conductor Julius Rudel, who has been associated with this work for half a century, adds both glamour and authenticity.

On one level, "Lost in the Stars" is a story of blacks and whites reconciling their differences. From a 21st-century perspective, however, Maxwell Anderson's libretto is dated and unintentionally racist.

The theme is inspiring, the score compelling if not quite this composer's top level, but the connecting dialogue is pretentious, preachy and tedious. At nearly three hours with the intermission, the work could do with some serious trimming.

A black man in South Africa murders a white man who has espoused the cause of blacks. The perp confesses his crime and is sentenced to death while his cohorts lie and are acquitted. At the end, the two fathers -- one a poor preacher, the other a wealthy separatist landowner -- reconcile their differences. The country hardly cries any less when the black preacher, having won the friendship of a white man, decides to stay on, but somewhere in all this there's meant to be a lesson about forgiveness and honesty.

Danila Korogodsky's excellent unit set -- high grass, with a dark, starlit backdrop -- creates the mood even before the drama begins. Rudel, who will be 87 on March 6, remains a venerable force, in full control of the 14-piece pit orchestra and large cast.

But it is the splendid 47-member chorus, sometimes as characters in the drama, more often as a Greek chorus on side platforms in the auditorium, that carries the show.

Superbly prepared by Stephen Neely (who also plays a small dramatic role), the choir has the evening's best music and packs the biggest punch, commenting on the drama and propelling it to the inevitable unhappy denouement. Choral diction is clear throughout, far more intelligible than that of any of the principals. As the leader of the chorus with prominent solo lines, Larry J. Giddens Jr. commands the ear with a stentorian high baritone that soars magnificently through the spaces of the theater.

Herbert Perry portrays the central figure, Stephen Kumalo, the preacher whose son commits a crime out of fear rather than malice, and his deep bass-baritone is persuasive for its intrinsic beauty despite fuzzy enunciation (sung and spoken). His twin brother, Eugene Perry (an accomplished baritone himself), is convincing in the speaking part of Stephen's son, Absalom. Most affecting is Dzidzofe Avouglan as Irina, Absalom's pregnant girlfriend.

This singer, a Californian of Togolese and Ugandan heritage, is a real find: a most appealing figure on stage with a thrilling soprano that conveys emotional truth along with a highly sensuous sound. Her aria, "Trouble Man," is a musical highlight that tears at the heartstrings.

Two engaging cameos provide the show's sparse moments of comic relief. Denise Sheffey Powell is feral and sexy in "Who'll Buy," a wonderful song with double-entendres on the fruits and vegetables she purports to be selling.

Later on, young W. Roger Randolph III steals focus as Stephen's grandson in his solo turn, "Big Mole." Unfortunately for both, the Byham acoustics work against their clever lyrics coming across the footlights.

"Lost in the Stars" continues at the Byham Theater, Downtown, at 8 tonight and 2 p.m. tomorrow. Tickets: $25-$75 (students $15); 412-456-6666 or www.pgharts.org.