function setVisibility(elem,state) 
{
	elemStyleObj = eval(getStyleObj(elem));
	elemStyleObj.visibility = state;
}
function hideAllSubNavs() 
{	
	setVisibility('aboutSubNavLayer','hidden');
	setVisibility('servicesSubNavLayer','hidden');
	setVisibility('technologySubNavLayer','hidden');
}
function showDefaultSubNav()
{
	if(document.defaultSubNav != null)
		setVisibility(document.defaultSubNav,'visible');
}
function showSubNav(elem) 
{
	hideAllSubNavs();
	setVisibility(elem,'visible');
}
// -----------------------------------------------------------------------------
// getDocObj
// 
// A basic document object constructor - taken from JavaScript + CSS + DOM Magic
// 
// Usage: variablename = eval(getDocObj(elementidvalue));
// -----------------------------------------------------------------------------
function getDocObj(elem,parent) 
{
	if (document.layers) {
	    if (parent) {
	     return "document."+parent+".document."+elem;
	      }
	    else {
		return "document."+elem;
		     }
		
	  } 
	    else if (document.all) {
		return "document.all." + elem;
	} 
	    else if (document.getElementById) {
		return "document.getElementById('" + elem + "')";
	}
}




// -----------------------------------------------------------------------------
// getStyleObj
// 
// A basic document style object constructor - taken from 
// JavaScript + CSS + DOM Magic
// 
// Usage: variablename = eval(getStyleObj(elementidvalue));
// -----------------------------------------------------------------------------
function getStyleObj(elem,parent) 
{
	if (document.layers) {
	    if (parent) {
	     return "document."+parent+".document."+elem;
	      }
	    else {
		return "document."+elem + ".style";
		     }
		
	  } 
	    else if (document.all) {
		return "document.all."+elem + ".style";
	  } 
	    else if (document.getElementById) {
		return "document.getElementById('"+elem+"').style";
		
	}
}