Jennifer Lopez sure knows her way around double-sided tape!

At Sunday's Academy Awards, the singer-actress, 42, and Cameron Diaz co-presented Oscars for Best Costume Design and Best Makeup.

The American Idol judge wore a typically daring dress -- a custom Zuhair Murad couture gown with a plunging neckline and cut-out sleeves -- that many watchers feared would expose more than Lopez bargained for.

Thankfully, Lopez (alongside Diaz, wearing a figure-hugging, strapless Gucci gown) did avoid a wardrobe malfunction -- although much of Twitter speculated otherwise.

Still, she didn't leave the stage totally unscathed. Presenting the first trophy, she and Diaz, 39, tried to pull off a joke. The sexy twosome turned their backs to the stage and looked over their shoulders with a knowing wink.

When the joke bombed, Diaz and Lopez broke into hysterics. Watch Lopez's near nip-slip and her failed joke with Diaz now.