The National Enquirer reports an on-set source that said, "During a break in filming, Will had gone to his dressing trailer to rest, but when he got there, he heard an eerie rattling noise - then strange voices coming from the bathroom."
Ferrell reportedly thought there were intruders in his bathroom, and that it sounded like someone having sex in there.
After security was called to check it out, Ferrell returned to the trailer "but once again, he heard the weird noises coming from the bathroom ... This time, he threw open the door and was shocked when he saw...NOTHING!" The source says that Ferrell announced, "It’s ghosts from that graveyard ... and I’m NOT going back in there." So the producers were forced to get the comedian a new trailer.
File this one under "as told by dubious source."