var state = 'none'; 

function showhide(layer_ref, img) { 

if (state == 'block') { 
state = 'none'; 
} 
else { 
state = 'block'; 
} 
if (document.all) { //IS IE 4 or 5 (or 6 beta) 
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); 
	hza.style.display = state; 
} 

if (document.getElementById(img).src=='downarrow.gif')
{document.getElementById(img).src='uparrow.gif';}
else
{document.getElementById(img).src='downarrow.gif';}
}