function roll(imageName, imageState) {
	if (document.images && loaded == 1) {
		tabOn = eval(imageName+"_"+imageState+".src");
	  	document [imageName].src = tabOn;
	}
}

if (document.images) {

	//top
		nav01_off = new Image();nav01_off.src ='navi_1.gif';
		nav01_on = new Image();nav01_on.src ='navi_1_on.gif';
		nav02_off = new Image();nav02_off.src ='navi_2.gif';
		nav02_on = new Image();nav02_on.src ='navi_2_on.gif';
		nav03_off = new Image();nav03_off.src ='navi_3.gif';
		nav03_on = new Image();nav03_on.src ='navi_3_on.gif';
		nav04_off = new Image();nav04_off.src ='navi_4.gif';
		nav04_on = new Image();nav04_on.src ='navi_4_on.gif';
		nav05_off = new Image();nav05_off.src ='navi_5.gif';
		nav05_on = new Image();nav05_on.src ='navi_5_on.gif';
		nav06_off = new Image();nav06_off.src ='navi_6.gif';
		nav06_on = new Image();nav06_on.src ='navi_6_on.gif';
		nav07_off = new Image();nav07_off.src ='navi_7.gif';
		nav07_on = new Image();nav07_on.src ='navi_7_on.gif';
		nav08_off = new Image();nav08_off.src ='navi_8.gif';
		nav08_on = new Image();nav08_on.src ='navi_8_on.gif';
		nav09_off = new Image();nav09_off.src ='navi_9.gif';
		nav09_on = new Image();nav09_on.src ='navi_9_on.gif';

	loaded = 1;
}