Long Usernames & Short mysql.user field

[cptsanity]

I've got the LONGUSERS variable set so that we can guarantee unique, easy to remember usernames. However, if the username is longer than 16 chars it gets truncated in mysql.user when the table is created and then phpmyadmin gives an authentication error when the user tries to access via cPanel.

Is there anywhere in the cPanel scripts that I can limit the mysql login to the first 16 characters of the username?

Thanks,

Chris