function montre(valeur) {
//alert (valeur);

	switch(valeur) {
		case('1'):
//			toggle_preview('d1');
			if (Element.visible('d2')) {
			new Effect.BlindUp(d2);
			}
			new Effect.BlindDown('d1', { queue: 'end' });

			return false;
			break;      
		case('2'):
//			toggle_preview('d2');
			if (Element.visible('d1')) {
			new Effect.BlindUp(d1);
			}
			new Effect.BlindDown('d2', { queue: 'end' });
			return false;
			break;      
                                                		
	}

} 

function initsel() {
	document.forms["form1"].choixext[0].checked = true;
	document.forms["form1"].choixext[1].checked = false;	
}

function toggle_preview(tgt) { 
	if (tgt != '') {
		var elem = $(tgt);
	}
	
	var elems = ['d1', 'd2']; 
	for (i=0; i< 2; i++) {
		if (Element.visible(elems[i])) {
			new Effect.BlindUp(elems[i]);
			if (tgt != '' && tgt != elems[i]) { 
				new Effect.BlindDown(elem, { queue: 'end' }); 
			}
			return;
		}
	} 
	if (tgt != '') {
				new Effect.BlindDown(elem, { queue: 'end' }); 
	}
}