"This is bulls***!" Sandra yelled upon taking the stage following Meryl's acceptance speech.
But the star soon showed her good humor, planting an on-the-lips kiss on Meryl that wowed the audience.
"Meryl's a great kisser," Sandra joked after, calling the award "an honor."
"It is a great honor to be in the company of the extraordinary women I was so lucky to be nominated with, because this one here inspired me to do everything better," she said.
For her part, Meryl, who won for "Julie and Julia," didn't think she'd gone to great lengths to embody her role.
"I love acting and I love to work and I love food and I love sex — so did Julia Child, so it wasn't that much of a stretch," she said.
Other winners at the awards show included "The Hurt Locker," for Best Picture; Jeff Bridges, for Best Actor in "Crazy Heart"; Christoph Waltz for Best Supporting Actor in "Inglorious Basterds"; and Mo'Nique for Best Supporting Actress for "Precious."
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