EXCLUSIVE

Former "Big Brother" star Krista Stegall -- who had some infamous drunken escapades -- got busted by cops for a major beef with her ex-husband.

Stegall was arrested in Louisiana on Wednesday afternoon when cops spotted her and realized there was a warrant out for her in a neighboring town. Law enforcement sources tell us she allegedly filed a false police report against her ex-husband, claiming his house was unfit for their children.

We're told her ex's pad was fine when cops checked, and that's when the warrant was issued. Police booked Stegall for criminal mischief and unlawful entry -- she allegedly tried to get into his crib at some point.

Back in Season 2 of 'BB' ... Krista got wasted and made out with housemate Justin, who then held a knife to her throat, and got booted from the show. Good times.