[Dovecot] How to use DoveCot with checkpassword

Hi,

im a newbee using dovecot. I want to use checkpassword, but i've no idea how to use it.

DoveCot is running and checking the passwords with a ldap server. But in future we want to use a sql database, where the password and userinformation is stored.

I want to use checkpassword, to authetificate the users with the passwords. But ive no idea how a script for checkpassword can be. What should i write to the checkpassword file (actualy the file is empty).

The SQL Database is on another server. Can i use PHP for checkpassword, and if i can, how should it be written. Which variables can i use and what and how shoul i return the result?

Greetings, Muhammed