Supernatural - Episode 6.15 - The French Mistake - Synopsis

I don't watch Supernatural, so I wouldnt know if this kinda episode is possible. I thought that this synopsis might have been fake at first, but I found similar synopses from 2 diff sites. I trust tv.com, I think.

TVRage:
Dean and Sam find themselves in an alternate reality where everyone believes they are two actors named Jensen Ackles and Jared Padalecki, who star in a TV show called Supernatural about two brothers who hunt monsters.

Guest Stars: Brian Doyle-Murray as Eric Kripke, Genevieve Cortese as Genevieve Cortese

TV.com
Sam and Dean are transported to a parallel world where they are mistaken for two actors named Jared and Jensen, who star in a TV series called Supernatural, which is about two brothers who hunt monsters for a living.

Sources: TVRage & TV.com