The most interesting thing about Donn Pennebaker's documentary film of the 1971 Town Hall debate between Norman Mailer and four feminists is how dated it seems.

The picture, "Town Bloody Hall," which showed to a packed house at the American Film Institute theater Wednesday night on a one-time-only basis, is strictly a curiosity.

That year, one recalls, there was a great storm over Mailer's article, "The Prisoner of Sex," which he claimed nearly killed Harper's magazine, causing most of the staff to quit in protest. But can you imagine, today, the likes of Germaine Greer and Jill Johnston and Diana Trilling consenting to go onstage with "Mr. Mailer," as he was called, for a debate on his attitudes toward women? With Mailer as moderator?

These days, fossils like Mailer are allowed to fume and blow smoke, either ignored or observed as casually as those Fourth of July snakes that excrete themselves on the sidewalk.

The star of the show was Greer, who managed to get in some sharp, cool comments when Mailer wasn't usurping other people's time, rambling on about his writing, making catty remarks, turning violent when attacked ("Either play with the team or pick up your marbles and get lost!") and going all boyish and cute when that didn't work.

Jill Johnston, reading one of her punning poems ("lesberated women"), spoke of the need for a "withdrawal of women to give themseves a new sense of self . . . Until all women are lesbians, there will be no true political revolution." She ran over her 10 minutes. Mailer wouldn't let her finish: "You've read your letter; now mail it!"

"What's the matter?" laughed Johnston, "are you afraid of women you can't f---?"

At that point two other women rushed up and embraced Johnston with some intensity. They wound up on the floor and finally left the scene entirely.

Trilling, who said she would take "Mailer's poeticized biology in perference to the nonbiology of my sisters," was called a traitor by some women in the audience, leading Greer to point out that "One characteristic of oppressed people is they always fight among themselves."

The audience in general seemed emotional from the start. One excitable man had a little fit when Jacqueline Ceballos spoke of women "fighting for all of humanity" and threw himself out of the hall. By contrast, the AFI audience seemed to find Mailer basically funny.

One wondered, in fact, if the 1980 audience wasn't regressing a bit, hissing automatically at every mention of the word "housewife" and hooting at every Mailer crack without apparently questioning why this self-promoter was being given the time of day, let alone center stage. A man could ask, for instance, if he really wanted Norman Mailer as spokesman for the entire sex under any circumstances.

Another curiosity of the film was that everyone in the New York hall, pros and cons, appeared to accept that red-flag phrase "women's lib" without hesitation. Evidently in 1971 it wasn't yet generally realized that the term was used by opponents (men, that is) to ghettoize the feminist movement, making it all too difficult for some women to stand up for their feelings ("you're not one of them women's libbers, are you?" "Oh nooo . . . .").

After the "formal" debate (Mailer: "I'm not gonna sit here and listen to you harridans harangue me"), some other feminist leaders were discovered in the audience. Betty Friedan noted that women speak in many different voices and don't all agree. Susan Sontag objected to Mailer's consistent use of the work "ladies" to describe them.

"I don't like being called a lady writer," she said. "It's a little better being called a woman writer. Would you call James Baldwin a Negro writer?" Other voices joined in: Would you call him a "man writer?" a "gentleman writer?" and so on.

Mailer, promising never to use the word again in public, promptly committed another howler when he described critic Trilling as "the best in kind," adding that "women haven't been critics as long as men." The laughter got so ferocious that he started talking about his penis.

Gradually he seemed to tire ("what I was trying to say . . . "), and the conversation ran on to his household as described in his article. Snapped Greer: "It consisted of four nurturing females and three boys, that is your two sons and you yourself." He called that a cheap shot. When asked how much housework he actually did, he admitted that after two weeks he called in his mistress to help. That brought the house down.

The parting shot: critic Anatole Broyard, from the audience: "I really don't know what women are asking for . . . . "

Greer: "Whatever they're asking for, honey, it's not for you."