function imatgeFons() {
	images = new Array(6);

	images[0] = "01";
	images[1] = "02";
	images[2] = "03";
	images[3] = "04";
	images[4] = "05";
	images[5] = "06";

	index = Math.floor(Math.random() * images.length);
	
	$("#container_sub").attr('style','background: #fff url(media/comu/random_estruch_f'+images[index]+'.jpg) 23px 24px no-repeat;');
	
}
$(document).ready(imatgeFons);