var imgLoaded = false;

	if (document.images) {

		var nav1_active = new Image();
		var nav1_inactive = new Image();
		nav1_active.src = 'images/nav/home_act.gif'
		nav1_inactive.src = 'images/nav/home.gif'

		var nav2_active = new Image();
		var nav2_inactive = new Image();
		nav2_active.src = 'images/nav/competitie_act.gif'
		nav2_inactive.src = 'images/nav/competitie.gif'

		var nav3_active = new Image();
		var nav3_inactive = new Image();
		nav3_active.src = 'images/nav/teams_act.gif'
		nav3_inactive.src = 'images/nav/teams.gif'

		var nav4_active = new Image();
		var nav4_inactive = new Image();
		nav4_active.src = 'images/nav/fun_act.gif'
		nav4_inactive.src = 'images/nav/fun.gif'

		var nav5_active = new Image();
		var nav5_inactive = new Image();
		nav5_active.src = 'images/nav/sarto_act.gif'
		nav5_inactive.src = 'images/nav/sarto.gif'

		imgLoaded = true;
	}

var keepActivenav1 = false;
var keepActivenav2 = false;
var keepActivenav3 = false;
var keepActivenav4 = false;
var keepActivenav5 = false;

function imageInact(itemName) {
	//alert(document.getElementById(itemName).src)
	if(imgLoaded && eval('keepActive' + itemName) == true) {
		document.getElementById(itemName).src = eval(itemName+'_inactive.src')
	}
}

function imageAct(itemName) {
	if(imgLoaded) {
		var strAct = '_act';
		var strSource = document.getElementById(itemName).src;
		if(!isValid(strAct, strSource)) {
			eval('keepActive' + itemName + '=true;');
		}		
		document.getElementById(itemName).src = eval(itemName+'_active.src')
	}
}

function isValid(string,allowed) {
    for (var i=0; i< string.length; i++) {
       if (allowed.indexOf(string.charAt(i)) == -1)
          return false;
    }
    return true;
}