You said you are using MySQL 4.0.24. My comments are based on that and your posted code.
* Note 1: Please take lots of time to read the MySQL Reference Manual [dev.mysql.com] as it details changes and proper usage. It does take digging :-) but the info is there.
* Note 2: My comments/additions/code suggestions are guidelines only. While I believe they are correct I have not referenced them - please take the time to confirm their validity.
safe-show-database - is deprecated (from 4.0.2) now being enabled by default - if necessary, use the SHOW DATABASES privilege to control access to database.
innodb_data_file_path=ibdata1:10M:autoextend - InnoDB is enabled by default (from 4.0). Note: some OS or associated sub-systems can cause conflicts - run "kill" tests early in development to confirm host servers won't crash, corrupt data, etc. - if OS = Linux disable the write-back cache.
ft_min_word_len=2 - including declaration in both [mysqld] and [myisamchk] (see below) ensures both myisamchk and the server use the same full-text parameter values.
[safe_mysqld] - renamed [mysqld_safe (from 4.0), there is supposed to be a symbolic link for legacy reasons but ... renaming is safer.
err-log=/var/log/mysqld.log - renamed log-error=/var/log/mysqld.log (from 4.0.10)
ft_min_word_len=2 - including declaration in both [myisamchk] and [mysqld] (see above) ensures both myisamchk and the server use the same full-text parameter values.