It's not easy to keep a secret in Hollywood, especially one involving a potential love connection between a not-quite-divorced Oscar winner and a dreamy-eyed pretty boy, but rumors continue to swirl that Reese Witherspoon and Jake Gyllenhaal, who co-star in the forthcoming drama "Rendition," are surreptitiously seeing each other.

"They are 100 percent dating," a "close insider" avows to Perez Hilton. "Reese and Jake are being smart about things and keeping their relationship very discreet and out of the public eye."

(Except, of course, for those pesky sources who are flapping their gums about how "smart" and "discreet" they're purportedly being, but moving on ...)

"Extra" says the soon-to-be-ex Mrs. Ryan Phillippe, 31, and the "Brokeback Mountain" thespian, 26, have recently been spied at one another's homes, supposed sightings that come about three weeks after OK! magazine reported they rendezvoused in New York.

But before you dub them with an annoying nickname (we're partial to GyllenSpoon), keep in mind that the paparazzi who constantly shadow Reese, whether she's taking kids Ava, 7, and Deacon, 3, to church or shopping with pal Jennifer Garner, have somehow failed to capture her alleged quality time with Gyllenhaal.

For now, their reps are mum on the dating nattering, although Jake, whose capricious coupling with Kirsten Dunst ended in 2005, has been vocal about his desire to achieve domestic bliss.

"Look, the most important job for a man is to find the right woman. It's the best we can do," he told GQ earlier this year. "I thank my father for choosing my mother. She's wonderful in so many ways. And she chose well, too. I've noticed in life that the mother, first, has a primary job -- and as a father, your job is to pick a caring, smart, mindful woman."

As for Jake's ex, those reports dubbing Dunst "smitten" with Johnny Borrell appear to be right on the money, because she recently flew several thousand miles just to gaze adoringly at him.

People reports the snaggle-toothed "Spider-Man" starlet, 24, was smiling "like a maniac" while watching her latest floppy-haired hipster beau, 26, perform with his band Razorlight in London a few days back.

"She was standing to the right of the stage and jumping and clapping her hands and smiling," an onlooker tells the mag. "She also sung along to the tracks."

Kirsten, who met Johnny earlier this month when his band played in Los Angeles, also winged to Austin, Texas, two weeks ago to join him for some PDA at the South by Southwest music festival.

"This relationship is the real thing," a snitch adds to the London Sun, before unkindly adding that the actress is following around the singer "like a lovesick puppy."

According to the source, the hot and heavy honeys "hated being apart and on Friday she flew to London and is staying in his flat. No one is sure how long she will be here for. She is filming in Europe soon so she could be in London a fair bit."

Dunst is quickly adjusting to English life, according to People, which says she and Borrell have been spotted munching on bangers and mash and quaffing pints at a couple of local pubs.

"She was very smiley," a pub spy tells the mag. "They both were. They were in their own little world."

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