I could not find a single article on it, actually I looked for 5 minutes and grew desperate. So I decided to tinker around. My beta install is on /opt/mysql_5.0_beta with a symbolic link on /usr/local/mysql. I had installed the database according to the installation directions.
I unpacked the release candidate to /opt/mysql-standard-5.0.13 and copied over all my data folder from my beta install. I then had to do a: