function newsletter_install() {
	var fld = document.getElementById('mail');
	if( fld ) {
		fld.onfocus = function() { erase(this); };
                var btns = document.getElementsByClassName( 'submit' );
		if( btns ) {
 			  for( var i = 0; i < btns.length; i++ ){
			    btns[i].onclick = function() { return verif_email( fld ); };
			}
		}
	}
}