// get element by ID (with browser check)
function getObj(objID){
	if (!document.getElementById)	return null;	// not compatible
	//else
	return document.getElementById(objID);
}

// show and hide DIV
function alternateShow(divToShow,divToHide) {

	// hide
	if (divToHide!=null&&divToHide.style!=null) {
		divToHide.style.display = "none";
	}

	// show
	if (divToShow!=null&&divToShow.style!=null) {
		divToShow.style.display = "block";
	}
}
		// cambio tab
		var oldtab="tabcontact";
		function swapTab(newTab)	{
			if (oldtab==newTab)	return;
			var obj=getObj(newTab);
			if (!obj)	return;
			alternateShow(obj,getObj(oldtab));
			oldtab=newTab;
		}
		
		var oldLog="";
			function swapLog(newLog)	{
			if (oldLog==newLog)	return;
			var obj=getObj(newLog);
			if (!obj)	return;
			alternateShow(obj,getObj(oldLog));
			oldLog=newLog;
		}
		    //-->