Thursday February 27, 11:46 AM

Buffy: So Long Sunnydale

With her contract up in May, the actress will let the sun go down on Sunnydale at the end of this season, in order to concentrate on her big-screen career.

Earlier this week it was announced that Gellar was close to signing on to the feature film Romantic Comedy. Production on the lovestruck spoof starts in August, ostensibly when Buffy would start filming on its eighth season. The casting news put a stake through Gellar's return to the UPN series.

Then in today's Variety, a report confirmed that the 25-year-old had broken the news to her Buffy boss, Joss Whedon.

Gellar won the role of the Chosen One back in 1997 when Buffy the Vampire Slayer was nothing more than a punchline, based on the box-office bomb starring Kristy Swanson ( news) and Luke Perry ( news) (how bummed are they not to have signed on for the series?).

Prior to Buffy, Gellar was best known for her sudsy role as Kendall Hart, daughter of scheming Erica Kane (Susan Lucci ( news)) on All My Children, for which she won a Daytime Emmy.

Despite its dedicated fan base, Buffy would never win the thespian an Emmy (or even a nomination), but during her seven-season tenure Gellar managed to add multiple credits to her résumé. While pulling double duty as wisecracking schoolgirl and vampire slayer, Gellar also moonlighted during her hiatus in movies like Scream 2, I Know What You Did Last Summer, Cruel Intentions, Simply Irresistible and Scooby-Doo.

Gellar's break-neck schedule is unlikely to slow down, with the actress slated to begin production on Scooby-Doo Too with husband Freddie Prinze ( news) Jr. as soon as Buffy wraps. Warner Bros. is eyeing a summer 2004 release for the sequel with a script already in the works for the third installment of the franchise.

Rumors of Gellar's departure had lurked on the Internet since last summer, when news that Buffy's sister Dawn (Michelle Trachtenberg ( news)) would have a larger role in the seventh season, prompting speculation that the demon-battling heroine would pass the stake on to her little sis.

Most recently, Eliza Dushku ( news)'s name was put forward as a possible slayer sub for a potential spinoff series. Dushku joined the Scooby gang in the third season as rogue Slayer Faith, but an alliance with the dark side put an end to her time in Sunnydale.

Ultimately, the Hellmouth could go unprotected since a rep for the actress just confirmed she's inked a pilot deal with Fox for an untitled project from writer John Feldman, which would see Dushku as a morgue employee who talks to the dead instead of staking them. The corpses tell Dushku's character how they were murdered and every morning she relives the same day, hoping to set things right.

In addition, Buffy's executive producer Marti Noxon has already been tapped for a new one-hour drama next season, leaving the fate of Sunnydale uncertain.

Still producers maintain the possibility that the slayer mythology lives on. "There's also been discussions about other characters," Chris Buchanan, president of Mutant Enemy, which produces Buffy and Angel, told E! Online two weeks ago when asked about a possible Dushku spinoff. "We're definitely exploring a couple of options but it's not at a deal stage yet because the other things have to happen first."

And in totally unrelated news, I thought the following story was pretty amazing!

By JILL LAWLESS, Associated Press Writer

LONDON - A man whose sperm was accidentally used to impregnate a woman at a fertility clinic is the legal father of her twin babies, a British High Court judge ruled Wednesday.

Dame Elizabeth Butler-Sloss said that under the Human Fertilization and Embryology Act, the biological father — a black man identified only as Mr. B — was the legal parent of mixed-race twins born to a white couple, Mr. and Mrs. A.

The judge stressed that Mr. and Mrs. A remained the children's social and psychological parents. She said the twins "have been loved by Mr. and Mrs. A and their wider family from the moment of their birth and nothing that has happened since then will change that."

The ruling did not decide custody arrangements for the babies, born after Mrs. A received sperm from a man undergoing treatment at the same clinic. Butler-Sloss said the twins "should remain with the family into which they were born, with Mr. and Mrs. A."

Andrea Dyer, a lawyer for Mr. and Mrs. A, said the couple would seek to adopt the twins to give Mr. A legal rights over them.

"The couple feel blessed that they have two beautiful children and Mr. A will continue to treat them as his own," she said. "They feel a great deal of sympathy for Mr. and Mrs. B."

The judge said a family court would have to decide how much access Mr. B would be given to the children.

The mix-up occurred at the Assisted Conception Unit of Leeds General Infirmary in northern England.

The two couples were at the clinic on the same day to receive a treatment known as intracytoplasmic sperm injection, in which sperm is injected into an egg and resulting embryos are implanted in a woman's uterus.

Sperm from Mr. B was inadvertently used to fertilize eggs from Mrs. A, who became pregnant. Mrs. B did not become pregnant.

After the error was discovered, fertility clinics were ordered to take extra precautions, including ensuring that two people witness every step in the procedure at which a mistake could be made.

Suzi Leather, chairwoman of the Human Fertilization and Embryology Authority, said it was possible similar mistakes had gone unnoticed because both biological parents shared the same racial background.

"It is impossible to say whether this would ever happen again. It is the only case we know of," she told British Broadcasting Corp. radio. "Intuitively, you might conclude it may not be the only time it's ever happened, given that there is an issue of mixed race here."

In 1998, New Yorker Donna Fasano gave birth to twins — one black, one white — after the wrong embryo was implanted in her womb. The white child was her biological son; the black child was no relation, and his biological parents won custody of the infant.