Switch from MySQL5 to MySQL4
 

I'm currently running ISPconfig on my Fedora Core 5 server and I'm using X-cart. The version I purchased requires MySQL4 and is not compatable with MySQL5. Currently, I have MySQL5 on my server and I would like to switch back to MySQL4 without corrupting any of the other MySQL dependencies such as PHP, dovecot, etc. Also, I've backed up my /var/lib/mysql directory so I won't lose any of the databases.

Does anyone have an easy transition for this?