SAN DIEGO -- James Cameron's movies are more than big-budget, futuristic action adventures.

"All of my movies are chick flicks," the filmmaker said in a "Today" show interview. "I can't help it. 'Aliens' was a chick flick. So were the 'Terminator' films. ... I love strong female characters. I love writing complex women."

By that standard, "Avatar" is a chick flick, too.

Sigourney Weaver and Zoe Saldana, the lead actresses of "Avatar," said as much at Comic-Con International over the summer, when they introduced a chunk of the film that opens today.

As Ripley in Cameron's 1986 "Aliens," Weaver set a high bar for strong, female characters in the sci-fi genre. As Grace Augustine in "Avatar," she plays a botanist who runs the Avatar Program on Pandora.

The actress volunteered that she worked on the making of Grace's action figure but hasn't seen the finished product.

"I hope there's a few little bits of plants and things like that," Weaver said. "It's good for girls to see that there's a woman scientist who's so good at what she does."

Cameron has created juicy roles for actresses over the years, including Linda Hamilton's protective mother in "Terminator" and Kate Winslet's Rose, the willful girl who defies convention in "Titanic."

To explain his adept way with action heroines, Weaver focused on the other major female characters in "Avatar" -- Saldana's Neytiri, a tall blue native Na'vi of the planet Pandora, and Michelle Rodriguez's Trudy, a pilot who shuttles humans and avatars from the Avatar Program's base to science sites on Pandora.

"He respects women," Weaver said of the writer-director. "He knows we're smart, we're strong, we go for it. He's just so OK about us being who we are, and I think only Jim could have written a character as fierce and tender at the same time as Neytiri. And grace ... there's so much grace in this woman who gives up her whole life to concentrate on this thing she believes in, that is her passion. It's so moving and it has so much wisdom in it about how women are different from men."

Weaver said Cameron's attitude frees an actress to, as she says, "Go for it."

"He wants you to be fabulous. He wants you to be brave. Look at Michelle's character. She's such a hero. She's so cool, so tough, so off-hand" in bringing Trudy to life.

Later, Cameron described a trait of the Na'vi, and it speaks to this idea of striving for a deep understanding of character, of others in general.

"There's a big thing about 'seeing' in the movie," he says. "The Na'vi use a term which means, 'I see you.' But they're not saying, 'I see you.' They're saying, 'I see into you. I understand you.' So they equate seeing with understanding. The movie is very much about seeing through the eyes of others."

Cameron is a guy in touch with his feminine side, Saldana said, and that's why "Jim understands a woman and respects her. And I love that."

She wasn't sure that would be the case when she reported for work on "Avatar" two years ago.

"This man's a truck driver who's tech savvy, who's a sci-fi geek, who speaks in such big words that you need a dictionary just to have a conversation about the weather. ... What is it about him?" she asked rhetorically.

"I think he's very much in tune with his fragility, because he's a very sensitive bugger. He will see something, and it will drive him to tears. And he'll snap his fingers [to snap out of it]. And at the same time, too, he loves blowing up [stuff]. He lives for that. ... He's in tune with all of his energies."

Back in July, Saldana was still feeling the sweet success of J.J. Abrams' "Star Trek," in which she portrayed another strong woman, Uhura.

With Weaver, the conversation naturally turned to Ripley. The director of the original "Alien," Ridley Scott, has announced a prequel for 2011.

Weaver is protective of Ripley as it was written back in the day, which becomes obvious when she discusses her voice work in video games.

"It was fun [doing the 'Avatar'] game, much more satisfying than the one they tried to get me to do as Ripley, which was a lot of killing of human beings. I said, sorry, I don't kill human beings. I try to save them."

Weaver doesn't plan to reprise her Ripley role.

"What's the point? It's already been done," she said. "I hear they're going to do a kind of a prequel thing, and I'm glad Ridley's involved in it. [But] I think the creature has had its day."

Weaver, who turned 60 in October, doesn't have to look back. She hasn't fallen into the Hollywood black hole often reserved for women of a certain age who find parts drying up.

"Most of my parts frankly are men's parts that they decide to have me play," she said. "And that's great, because they're just people."

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