submenus = 3;
subsubmenus = 0;
browserv = (parseInt (navigator.appVersion) >= 4) ? true : false; // Browser-version 4 required

// Open or close submenu
function flipSub (subid, haveSubs)
{
 
 // Browser-version 4 is required
 if (browserv)
 {
  if (haveSubs == false) {
   closeSub (false);    // Close all submenus
 
   // Netscape 4.x
   if (document.layers)
    document.layers['sub' + subid].visibility = 'show';

   // Other browsers
   else if (document.getElementById)
   document.getElementById('sub' + subid).style.visibility = 'visible';
  } else { 
   closeSub (true); // Close only subsub menus  

   // Netscape 4.x
   if (document.layers)
    document.layers['sub' + subid].visibility = 'show';

   // Other browsers
   else if (document.getElementById)
    document.getElementById('subsub' + subid).style.visibility = 'visible';
  }
 }
}

// Close all submenus
function closeSub (onlySubSubs)
{
 var onlySubSubs = onlySubSubs;

 // Browser-version 4 is required
 if (browserv)
 {
  // Netscape 4.x
  if (document.layers) {
   if(onlySubSubs == false) {
    for (i = 1; i <= submenus; i++) 
     document.layers['sub' + i].visibility = 'hide';
  
    for (i = 1; i <= subsubmenus; i++)
     document.layers['subsub' + i].visibility = 'hide';
   } else {
    for (i = 1; i <= subsubmenus; i++)
     document.layers['subsub' + i].visibility = 'hide';
   }   
  }
  else if (document.getElementById)   // Other browsers
  {
   if(onlySubSubs == false) {
    for (i = 1; i <= submenus; i++) 
     document.getElementById('sub'+i).style.visibility = 'hidden'; 
  
    for (i = 1; i <= subsubmenus; i++)
     document.getElementById('subsub'+i).style.visibility = 'hidden'; 
   } else {
    for (i = 1; i <= subsubmenus; i++)
     document.getElementById('subsub'+i).style.visibility = 'hidden'; 
   }   
  }
 }
}

// Close all submenus
function closeAll ()
{

 // Browser-version 4 is required
 if (browserv)
 {
  // Netscape 4.x
  if (document.layers) {
   for (i = 1; i <= submenus; i++) 
    document.layers['sub' + i].visibility = 'hide';
  
   for (i = 1; i <= subsubmenus; i++)
    document.layers['subsub' + i].visibility = 'hide';
  }
  else if (document.getElementById)   // Other browsers
  {
   for (i = 1; i <= submenus; i++) 
    document.getElementById('sub'+i).style.visibility = 'hidden'; 
  
   if (submenus > 0) {
    for (i = 1; i <= subsubmenus; i++)
     document.getElementById('subsub'+i).style.visibility = 'hidden'; 
   }
  }
 }
}
document.onmouseup = closeAll;