Preload diffrent mc`s

Hi
I have a preloader that preloads the main_mc (movieclip) but I want to load also a diffrent movieclip with the same preloader the main2_mc. I am using this code for the preloader on the first frame:

this.onEnterFrame = function() {
filesize = main.getBytesTotal();
loaded = main.getBytesLoaded();
preloader._visible = true;
if (loaded != filesize) {
preloader.preload_bar._xscale = 100*loaded/filesize;
} else {
preloader._visible = false;
if (main._alpha<100) {
main._alpha += 10;
}
}
};