Duplicatemovieclip

i posted it the other day but i think it got deleted when kirupa switched hosts.

I have this code in the frame


button.onRelease = function() {
    circledup++;
    for (i=0; i<circledup; i++) {
        duplicateMovieClip("circle", "dupMC"+i, i);
        _root["dupMC"+i]._y = i*5;
    }
}

but i want the movie clip to duplicate when
circle, hitest(block)
thanks

bump