Amid rumors that ABC’s new “Pan Am” series is in the toilet because of low-flying ratings, cutie-pie star CHRISTINA RICCI actually got stuck in a toilet during a scene where she was supposed to exit the prop plane’s john and deliver a biting line – but suddenly could NOT open the door!

Worse, when she yelped, “Help, I’m stuck in here!”

Everyone laughed at first –

But when they attacked the door en masse, and couldn’t make it budge, a crew member attacked with a crowbar –

And finally busted the door open after declaring it “broken!”

(Like the series?)