function add_champ_pj()
	{  //Calcul du nombre de balises up_*
		var i = 1;
		while (document.getElementById("up_"+i)){i++;}
		// Creation d'un nouveau champs input de type file
		var new_elt = document.createElement('div');
		new_elt.id= 'up_'+i;
		var new_lab = document.createElement('label');
		new_lab.htmlFor ='contact_up_'+i;
		new_lab.innerHTML = 'Pièce jointe n°'+i+' : ';
		//var text_lab = document.createTextNode('Pièce jointe :');
		//new_lab.appendChild(text_lab);
		var new_br = document.createElement('br');
		var new_input = document.createElement('input');
		new_input.id = 'contact_up_'+i; new_input.className = 'contact_input';new_input.type='file';new_input.size ='30';new_input.name = 'contact_up_'+i;

		new_elt.appendChild(new_lab);
		new_elt.appendChild(new_br);
		new_elt.appendChild(new_input);
		// Insertion dans la page
		noeud_up = document.getElementById("up");
		noeud_up.appendChild(new_elt);
	}
function formToggle (e){
	e.stop();
	var disp =$('contact_form').getStyle('display');
	if (disp == 'none'){
		Effect.Grow('contact_form', {duration: 0.5, direction: 'top-left'});
		$('aff_button').update("Masquer le formulaire de contact");
	}
	else 
	{
		Effect.BlindUp('contact_form', {duration: 0.5, scaleX: true, scaleY: true, ScaleFrom: 100, scaleTo: 0});
		$('aff_button').update("Afficher le formulaire de contact");
	}
}
function initObs (e) {
	if ($('aff_button')) $('aff_button').observe('click', formToggle);
}
if (document.implementation.hasFeature('Core', '2.0')){
	document.observe('dom:loaded', initObs);
}