var state = 'none';

function showhide(layer_ref) {

if (state == 'block') {
state = 'none';
}
else {
state = 'block';
}

if (document.all) { //IS IE 4 or 5 (or 6 beta)
var divStyle = eval( "document.all." + layer_ref + ".style.display");
  if (divStyle == 'none') {
      state = 'block';
   }
   else if (divStyle == '') {
      state = 'block';
   }
   else {
      state = 'none';
   }
eval( "document.all." + layer_ref + ".style.display = state");
}
if (document.layers) { //IS NETSCAPE 4 or below
document.layers[layer_ref].display = state;

}
if (document.getElementById &&!document.all) {
hza = document.getElementById(layer_ref);
var divStyle = hza.style.display;
   if (divStyle == 'none') {
      state = 'block';
   }
   else if (divStyle == '') {
      state = 'block';
   }
   else {
      state = 'none';
   }
hza.style.display = state;
}
}