DBM authentication and PHP

[Anon]

I get advice to protect directory with DBM.
I created dbm file with PHP script:

$db = dbmopen("/home/domain/secret/test", "n");
dbmclose($db);

And than .htaccess file:

AuthDBMUserFile /home/domain/secret/test
AuthName Protected_Area
AuthType Basic
require valid-user

And now question. How to crypt password that will suit for authentication?

I know this could be done with perl script but I need PHP because I already
have PHP script for web aplication where user can change their password.

Thanks for any advice!
Anzej