Jodie Sweetin drug relapse

Sources on set of Jodie Sweetin's new D-list movie Port City claim the former Full House actress -- and admitted recovering drug addict -- is using again.

An on-set snitch says Jodie did cocaine with several film workers.

"I watched Jodie Sweetin snort cocaine. The door of the trailer was locked. We knocked on the door for a few minutes, and finally some guy let us in. Jodie was sitting on the couch. After a few minutes of conversation, Jodie announced: 'I have a surprise for you.' She led us to the back of the trailer where there was a white paper plate with a small pile of white powder and a rolled-up $20 bill beside it," the inside source says. "Jodie said she'd just bought about $50 worth of cocaine from some local guys who'd been hanging out in the seedy neighborhood where we'd been filming. We each took turns cutting a line of coke and then snorting it. I witnessed Jodie snort at least two lines of cocaine."

The National Enquirer says this source passed a lie detector test.

Sweetin's estranged husband Cory Herpin salivated at the news, prepping to use it against his ex at a custody hearing for the couple's infant daughter Zoie on February 9.

"If Jody is using drugs I want full custody of Zoie," says Herpin. "I'm concerned for our daughter's well-being. Jodie cannot be trusted to make good decisions when she's drunk or high."

Just last week, Sweetin insisted to People that she's clean and sober.

"There are a lot of things being said about my using that are not going on right now. I want to make it known that I am absolutely, 100 percent sober."

But Herpin differs. "She has continuously broken her sobriety since Zoie was born," he claims in court papers.