Treehouse Of Horrorfest starting tonight?!?

I have seen these commericals for this the last few hours on Comedy. Itays "The Simpsons Treehouse Of Horrfest starting tonight at 9:00!" However when i check my guide it says the episode playing at 9 tonight is "Stark Raving Dad" and it's not a treehouse of horror special or even a halloween themed episode, it's the one with michael jackson. the rest of the week has treehouse of horror's on my guide starting with "treehouse of horror ll" tomorrow. I don't want to miss the first one, does anyone know what's going on????? thanks