Problem with buttons interacting with movies

ok. I have a problem.

I have three buttons next to each other . when i rollover on one of them it goes down. buttons are animated, so it really goes down, rather than just appears there. other buttons does the same, but they do it somekind wierdly. they first go down and then up.

If someone could tell me how to "tell button1 in the movie1, that IF button2 in the movie2 is up, don’t do anything, and IF it is down, it should get up…

in other words, "if movie2 is on a frame 10 don’t do anything, but IF it is on a frame 20, then go in to frame 21.

code from movie1’s button1,:

on (rollOver) {
play();
tellTarget (_root.movie2) {
gotoAndPlay(21);
tellTarget (_root.movie3) {
gotoAndPlay(21);
}
}
}

it does just what it says, but i can’t do it any other way. It shouldn’t jump in the frame 21, if it is on frame 15.

HELP!!! and ask for more information if you need.

thank yous.