var actab = 1;

function img_sw(obj, img, tab) {
	if (tab == actab) return;
	obj.src = img;
}

function nav_sw(tab, lang) {
	actab = tab;
	for (i=1; i<5; i++) {
		if (i != tab) {
			document.getElementById('tab'+i+'a').className = 'invisible';
			document.getElementById('tab'+i+'b').className = 'invisible';
			if (document.getElementById('tab'+i+'c')) document.getElementById('tab'+i+'c').className = 'invisible';
			var x;
			if (i<10) x = '0'+i;
			else x = i;
			img_sw(document.getElementById('imgnav'+x), STATIC_LIMAGES+'/cat_'+x+'b.gif');
		}
		else {
			document.getElementById('tab'+i+'a').className = '';
			document.getElementById('tab'+i+'b').className = '';
			if (document.getElementById('tab'+i+'c')) document.getElementById('tab'+i+'c').className = '';
		}
	}
}