function displayDiv(theDiv) {
	
 if (document.getElementById(theDiv)) {
	document.getElementById(theDivCurrent).style.display = "none";
	document.getElementById(theDiv).style.display = "block";
	document.getElementById(theDivCurrent+'_').className = "psinactive";
	document.getElementById(theDiv+'_').className = "psactive";
	theDivCurrent = theDiv;
 }
}