Upgrade FC4 to FC5

I find some following resources from the web:

http://www.linuxsky.net/html/200604/2635.html
http://www.brandonhutchinson.com/Upgrading_Red_Hat_Linux_with_yum.html


ext3 upgrade:
http://archives.free.net.ph/message/20060508.023346.df45ee08.en.html