Joaquin Phoenix is a 'fraidy cat. The Oscar nominee ("Gladiator"), currently starring with Mel Gibson in last weekend's No. 1 movie at the box office, director M. Night Shyamalan's "Signs," confesses to having been frightened by the flick when he finally saw it at a screening. "It's kind of embarrassing, but I did jump a few times," Phoenix, 27, told reporters, according to the Associated Press. "I was pretty scared. And I laughed, I think Mel is so funny. " As for how a project that he had been with for so long could still take him by surprise, he said: "You work on a film, and you see 20 takes. When it's all put together, it's all flowing, there's a continuity. And if it's done right, you get just as swept away as anyone else." He also revealed that the dog in the movie, who reacted with fright every time the aliens were in the cornfield, was trained to bark on cue and behave scared. "We did the first take and everything was splendid," Phoenix said. "And Night said to me, 'Wow! You're really great with animals.' And I'm really superstitious. And I said, 'No! You jinxed it. Don't say that.'" No comment from the dog.