After installing mysql on Mac Os 10.5.8, I could connect to the mysql server from the command line.
But when I tired to open phpmyadmin I got this error:

Error: The server is not responding (or the local MySQL server’s socket is not correctly configured)

Solution that worked for me:

1. sudo mkdir /var/mysql
2. sudo ln -s /private/tmp/mysql.sock /var/mysql/mysql.sock
3. restart apache