var lastOpenned = 0;
function turnOffMenu()
{  
		var vis;  
	if( lastOpenned ) {
		vis = lastOpenned.style;
		vis.display = 'none';
	}
	lastOpenned = 0;
}

function turnOnMenu( whichMenu )
{  
	turnOffMenu();

		var elem, vis;  

	if( document.getElementById ) // this is the way the standards work    
	{
		elem = document.getElementById( whichMenu );
	}
	else if( document.all ) // this is the way old msie versions work      
	{
		elem = document.all[whichMenu];  
	}
	else if( document.layers ) // this is the way nn4 works    
	{
		elem = document.layers[whichMenu];  
	}

	if(elem)
	{
		vis = elem.style;  // if the style.display value is blank we try to figure it out here  
		vis.display = 'block';
		lastOpenned = elem;
	}
}