YOU AIN’T MY MOMMA! MERYL STREEP, cast and crew can’t stop rolling their eyes at the diva antics of JULIA ROBERTS, who plays Meryl’s daughter in their new flick, “August: Osage County.”

On location in Oklahoma, both Academy Award-winning stars get fancy-schmancy contract perks like daily flowers in their dressing trailers, special gourmet meals, flat-screen TVs, high-end sound systems, exclusive hair and makeup people, etc. – but when Julia arrived, she instantly bitched that Meryl’s dressing trailer was better than hers and demanded a new one.

“That made Julia happy for about five minutes,” reports my roving reporter, Onda Settalott.

“But then she complained that Meryl’s trailer was closer to the actual set than hers. That really made everyone groan – it was closer by just a few FEET!

"But Julia insisted, so the crew were summoned to make her trailer exactly even with Meryl’s. It’s been one thing after another with Julia, but Meryl just smiles and never says a word. She’s a total pro and won’t let herself get caught up in what she’s privately called ‘childish antics.’ ”

(But things are never equal: Meryl’s won three Oscars, with a whopping 17 nominations; Julia’s won once, with three nominations.)