Maybe it’s because he has to wake up so early. Or maybe he just doesn’t like Kevin Smith.

Either way, one thing’s certain: “Good Morning America” film critic Joel Siegel really, really hates “Clerks II,” set to open Friday at theaters across the country.

Sitting in the front row of a packed midtown Manhattan screening room Monday night, Siegel dramatically stood up only 30 minutes into the film and stormed out, to the amazement of those in attendance.

And he didn’t go quietly.

“Time to go!” he yelled as he stood up and proceeding to walk out, passing dozens of critics and writers on his way to the door. And his tirade continued all the way out, as he yelled over the film’s dialogue that this was the first time “in thiry (expletive) years” he had walked out on a film.

The apparent reason for Siegel’s vulgar outburst? A line of dialogue in the film – well, one of many, actually – about sex between a woman and a donkey. Later in the screening, one other unnamed critic appeared to make an early departure.

Only time will tell what Siegel has to say about the episode on “GMA” this Friday.

DON’T joke about women, donkeys and bestiality if you expect Joel Siegel to watch your movie. That’s what director Kevin Smith found out when the pun-loving “Good Morning America” film critic stormed out of a press screening of Smith’s “Clerks II,” which opens Friday – an act that’s sparked a vicious war of words between the two.

“Time to go!” roared Siegel to his fellow critics. “First movie I’ve walked out of in 30 [bleeping] years!” His tirade came 40 minutes into the long-awaited Weinstein Company sequel to Smith’s 1994 cult classic about two foul-mouthed Long Island convenience store clerks who razz customers and goof off.

In the scene that sent Siegel to the exit, the characters graphically discuss hiring a woman to perform sexual favors on a donkey. Siegel told Page Six: “It was so foul and mean and repulsive. I finally realized I could not say anything positive . . . I wasn’t ready for this kind of smut . . . I hope he doesn’t make any more movies.”

An apoplectic Smith fired back on his MySpace blog: “Getting a bad review from Siegel is like a badge of honor. This is the guy who stole his mustachioed-critic shtick from Gene Shalit years ago, and still refuses to give it back. This is a guy who seemingly prides himself on his own nyuk-nyuk wordplay. For ‘Pirates 2,’ he made us all titter with ‘Yo, Ho, Ho and a Bottle of Fun’ . . . He made us squeal with delight when he wrote, ‘Wheelie Good Time for “Cars.” ‘ I mean, Fozzy [bleeping] Bear laughs at this guy.”

And there’s more: “I don’t need Joel Siegel to [bleep] my [bleep] the way he apparently [bleeps] M. Night Shyamalan’s, gushing over his flick [‘The Lady in the Water’] before he’s even seen it, but [bleep] man, man – how about a little common [bleeping] courtesy? You never, never disrupt a movie, simply because you don’t like it. Cardinal rule of moviegoing: Shut your [bleeping] mouth while the movie’s playing.

“I don’t come down to your job and slap the taste out of your mouth for coming up with a line like, ‘ “Shark Tale” Is a Halibut Good Time’ – so don’t [bleep] with my stuff while it’s still screening . . . What are you, a 12-year-old boy cutting loose with your pals at a Friday night screening of ‘Scary Movie’ 4′ while your parents are in a theater down the hall watching ‘The Devil Wears Prada’? Leave the diva-like behavior and drama-queen antics to the movie stars, not the movie reviewer, ya’ rude-ass [bleep].”

So last night, at a press screening of “Clerks II” in New York City, “Good Morning America” movie critic Joel Siegel decided he’d had enough of my shenanigans, and walked out of the flick at the forty minute mark. You’d imagine this would bother me, and yet, I’m as delighted by this news as I was with the eight minute standing ovation “Clerks II” received in Cannes.

I mean, it’s Joel Siegel, for Christ’s sake. As Paul Thomas Anderson once said of the man, getting a bad review from Siegel is like a badge of honor. This is the guy who stole his mustachioed critic shtick from Gene Shalit years ago, and still refuses to give it back. This is a guy who seemingly prides himself on being “punny” – that is, he likes to add his own nyuk-nyuk wordplay into the reviews he writes/gives.

For “Pirates 2″, he made us all titter with “Yo, Ho, Ho and a Bottle of Fun”.

For Pixar’s lastest, he made us squeal with delight when he wrote “Wheelie Good Time for ‘Cars’”.

Can you believe he somehow not only made us laugh, but also think, when he challenged our perception with “X-Men’ Fails to X-cite”?

I mean, Fozzy fucking Bear laughs at this guy (AT, mind you, not WITH).

So while I feel like my life will be a little bleaker now that I’ll never know what pun Joel would’ve dug deeply into his comedic well to produce for “Clerks II” (”‘Clerks II?’ More like ‘Jerks, Too’!”), I’ve gotta admit that I’m relieved somebody was finally offended by the flick – enough to head for the exit less than an hour in. I was beginning to think I was losing my touch.

I can’t fault Mr. Siegel for feeling “revolted” (his producer’s description of Joel’s reaction) by our flick; in truth, there is a donkey show in it, and I recognize that brand of whimsy might not be for everybody. Film appreciation is very subjective, and maybe Joel just isn’t into ass-to-mouth conversations.

However, I CAN fault him for the manner in which he left the screening.

Apparently, rather than quietly exit, both Joel and his Cum-Catcher (my slang for the fancy kind of mustache he sports) made a big stink about walking out, calling as much attention to himself as possible, and being generally pretty disruptive.

Check this shit out: roughly forty minutes into the flick, when Randal orders up the third act donkey show, Siegel bellowed to his fellow critics “Time to go!” and “This is the first movie I’ve walked out of in 30 fucking years!”

Now, I don’t need Joel Siegel to suck my dick the way he apparently sucks M. Night’s, gushing over his flick before he’s even seen it; but shit, man – how about a little common fucking courtesy?Never mind the fact that when you’re paid to watch movies for a living and the only tasks required of you are to a) sit through said movies and b) write your thoughts about them before your deadline, walking out before a movie’s over is pretty unprofessional. Never mind the fact that the scene he was offended by (the ordering of the donkey show), with its (misleading) crude references is only the set-up to a third act pay-off that is a true bait-and-switch from where Joel’s imagination went (and if you’ve already seen the flick, you KNOW what I’m talking about). Never mind that this dude is so straight-laced in his tastes and hyperbolic in his praise that when The Onion took a poke at Joel, I was almost unsure whether it was a joke or not…

You never… NEVER disrupt a movie, simply because you don’t like it.

Cardinal rule of movie-going: shut your fucking mouth while the movie’s playing. They even ask you to do so in the pre-show run-up to every flick (”Cell phones and pagers off, no talking during the show”). This guy went beyond talking, even; he was making a spectacle of himself as he left. I’ve now spoken to three folks in attendance last night, and all have said that Siegel WANTED everyone to know how disgusted he was, and that he was leaving. If you want to share your displeasure with everyone, that’s fine, dude; just do it AFTER the movie, not during. Some folks were enjoying themselves. I don’t come down to your job and slap the taste out of your mouth for coming up with a line like “‘Shark Tale’ Is a Halibut Good Time”; so don’t fuck with my stuff WHILE IT’S STILL SCREENING.

Shit, Joel, I know you like being on camera and all, but was it so difficult to not be the center of attention for 40 minutes that you just had to sparkle, Neely, sparkle-it up for your peers instead of showing them a little goddamn courtesy by leaving the theater the way most people do, either during or after the picture: quietly? What are you, a twelve year old boy, cutting loose with your pals at a Friday night screening of “Scary Movie 4″ while your parents are in a theater down the hall watching “The Devil Wears Prada”? Leave the diva-like behavior and drama-queen antics to the movie stars, not the movie reviewer, ya’ rude-ass prick.

It makes me laugh to think that, had Joel stayed ’til the end (like any good critic would for any movie they’re paid to watch), he would’ve seen that we weren’t going where he seemed to think we were going. But apparently, Joel took a cue from his own “Poseiden” review, in which he wrote “Audiences today wouldn’t stand for an hour of exposition before the flood hit. In fact, they wouldn’t stand; they’d walk out.” Well, Magnum (y’know – because of the mustache), I guess you’re a member of that same audience that can’t stand exposition.

Look, I don’t hate the guy. Shit, I’m glad he survived his fairly recent bout with cancer. But his behavior in that screening was unconscionable and professionally unethical, not to mention childishly disruptive. And while I might get laughed at for saying this… well, I just expected more from Joel Siegel.

*sigh*