function OpenWindow (sUri, iWidth, iHeight)
{
	var sWindowName = 'win' + Math.floor (Math.random() * 1000)
	var iRealWidth = iWidth ? iWidth : 600
	var iRealHeight = iHeight ? iHeight : screen.height - 300

	var iLeft = Math.round ((screen.width - iRealWidth) / 2)
	var iTop =  Math.round ((screen.height - iRealHeight) / 2) - 35

	var sWindowOptions = 'status=no,menubar=no,toolbar=no'
	sWindowOptions += ',resizable=no,scrollbars=no,location=no'
	sWindowOptions += ',width='  + iRealWidth
	sWindowOptions += ',height=' + iRealHeight
	sWindowOptions += ',left='   + iLeft
	sWindowOptions += ',top='    + iTop

	var win = window.open (sUri, sWindowName, sWindowOptions)
	win.focus()
}