function na_show_layer(lname)
{
  if (na_show_layer.arguments.length <= 1) 
  { // don't delete, backword compatibility
    if(document.getElementById) {
      document.getElementById(lname).style.visibility = 'visible';
    } else if(document.layers) {
      document.layers[lname].visibility = 'show';  
    } else if(document.all)
      document.all(lname).style.visibility = 'visible';
	  var visibilite = 1;
  } 
  else {
    if(document.getElementById) {
      document.getElementById(lname).style.visibility = 'hidden';
    } else if(document.layers) {
      document.layers[lname].visibility = 'hide';   
    } else if(document.all)
      document.all(lname).style.visibility = 'hidden' ;
	  var visibilite = 0;
  }
}