I just download the prerelease 1.9 from this site and installed it and tryed to join the sever but it says "this sever out of date"

The prerelease only works with the prerelease server. The IP is in the news article (front page). To join the regular server, you need to be on 1.8. We don't update our server for the prereleases - only for the full releases (and Bukkit).

The 1.9 server is a different server:
http://crazy-fools.co.uk/news.php?item.234.4

The main server is still on 1.8 and will be until 1.9 reaches its final release. To revert, delete your .minecraft/bin folder and let minecraft re-download it

thanks