function closeChildWindow() {
	map.removeOverlay( tLayer );
	tLayer = "";
	new Effect.Shrink( 'board', { duration: 0.4 } );
}
function openChildWindow(e) {
	var board = document.getElementById('board');
	board.style.left = e.clientX + 'px';
	board.style.top = e.clientY + 'px';
	board.style.display = '';
	board.style.filter = 'alpha(opacity=70)';
	board.style.mozOpacity = 0.7;
	board.style.Opacity = 0.7;
}