function form_verif(form_id){
	
	// we define -----------------------
	form = document.getElementById(form_id);
	
	// we init -----------------------
	var keAlerte = "";
	
	// we verify -----------------------
	switch (form_id){
		
		
		case "form_contact" :
	
			if (form.nom.value == "" || form.nom.value == " ") keAlerte+="\n"+_LANG_plz_fill_last_name+"\n";
			if (form.prenom.value == "" || form.prenom.value == " ") keAlerte+="\n"+_LANG_plz_fill_first_name+"\n";
			if (form.email.value == "" || form.email.value == " ") keAlerte+="\n"+_LANG_plz_fill_email+"\n";
			
			if (form.email.value != "" && !verif_mail(form.email.value)) keAlerte += "\n"+_LANG_email_invalid+"\r";
			
			
		break;
	
	}
	
	
	// we act -----------------------
	if (keAlerte!=""){
		alert(keAlerte);
		return false;
	}else{
		form.submit();
	}
	
	
}