Hi Picco,
The page you have the example on has achieved this affect by putting new lines in the html source code.
This works fine in IE, but many other browsers will not render it this way.
If you need it to work in more browsers, you could use javascript to hide / show a div with your content. There is a basic example of this in the thread:
http://p2p.wrox.com/topic.asp?TOPIC_ID=15474
HTH,
Chris