I do not believe it is. The easiest thing to do is to download it from here (mysql.com) I install both it and the startup item included in the package.
"As a side note: when using Time Machine you may be interested in excluding the log files, which by default are hidden in a directory that even an admin account cannot access:
ls -la /usr/local/mysql-5.0.51a-osx10.5-x86 [..] drwxr-x--- 4 _mysql wheel 136 Jul 10 23:06 data [..]
Or, change the MySQL settings to move the logs to some temp folder.
(To remove existing MySQL log files from the backup disk, you need to run Time Machine as root.)"
