But, that's exactly what happened over the weekend as the Oscar-winning actor hung out with 'RHOA's Cynthia Bailey, Porsha Williams and Phaedra Parks in Miami, Florida.

Check out the footage posted Saturday to Porsha's Instagram ... Jamie is having a blast with the 'RHOA' cast and several other people at Prime 112 Restaurant.

In her IG caption, Porsha described the funfest as a "karaoke hour" with Jamie and the others singing famous songs and shooting cell phone videos around a table.

The group belted out -- among other tunes -- Aaliyah's “One in a Million” and Mariah Carey's “We Belong Together,” during which Jamie was seen showing off his vocal skills.

Jamie was also filmed sandpapering his hands together over Phaedra's booty as she put her dance moves on full display.

But, Jamie didn't stop there. He placed his hands above Phaedra's buns to mimic warming his palms over a campfire.

Porsha, meanwhile, used a huge knife with the blade turned down as a microphone, singing into the handle.

Of course, there was a lot more ... but you'll have to take a look-see for yourself.