crypt salt question

Hello, I'm trying to move some app from postgresql to mysql but unable to find out how to authenticate against the current crypted passwords with php.. insert to database: $cset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789./"; $salt = substr($cset, time() & 63, 1) . substr($cset, time()/64 & 63, 1); $password = crypt($password, $salt); //pass crypted version of password for further processing $result = pg_query ("INSERT INTO users (username, password) VALUES ('$username', '$password')"); I read the crypt is one way encryption but how to compare the password entered with the encrypted version if don't know the salt ?? Thanks, Andras