function launchWindow(url,name) {

		win=window.open(url,name)

	}

	

	function rollover(theimage) {

		document[theimage].src = eval(theimage + '_on.src')

	}



	function rollout(theimage) {

		document[theimage].src = eval(theimage + '_off.src');

	}

	

	function popupCentre(url,name,width,height) {

		var titleBarHeight, windowBorderWidth

		titleBarHeight = 24

		windowBorderWidth = 4



		var screenWidth, screenHeight

		screenWidth = 800

		screenHeight = 600



		if (window.screen) {

			if (window.screen.availWidth) {

				// ok browser has the appropriate properties we need to centre it

				screenWidth = window.screen.availWidth

				screenHeight = window.screen.availHeight

			}

		}



		var windowWidth = windowBorderWidth + width + windowBorderWidth

		var windowHeight = titleBarHeight + height + windowBorderWidth



		var left = (screenWidth - windowWidth) / 2

		var top = (screenHeight - windowHeight) / 2



		win=window.open(url,name,'left='+left+',top='+top+',screenX='+left+',screenY='+top+',width='+width+',height='+height+',scrollbars=0,resizable=0,toolbar=0,location=0,directories=0,status=0,menubar=0,copyhistory=0')

		if (parseInt(navigator.appVersion) >= 4) { win.window.focus(); }

	}