How to compare crypted password with stored in MySQL

Hi, I have a MySQL database with encrypted passwords, that were created with: $input_password = $_POST["password"]; $salt = "ab"; /// Salt is always two character string and the same for all $password_to_save = crypt($input_password, $salt); and then saved in MySQL with: insert into password_table set passwd='$password_to_save'; (other columns are inserted also, but passwd is the one related to this question). Now, to check if a password is valid, I set $salt as the first two characters of the stored encrypted password, and with this salt I crypt and compare both: $salt = substr ($password_stored_in_mysql, 0,2); $password_to_check = crypt($input_password, $salt); if ($password_to_check == $password_stored_in_mysql) echo "Password is the same"; This used to work on a PC that runs PHP 4.1.2 and MySQL 3.23.36. But when trying this on other PC that runs PHP 4.3.11 and MySQL 3.23.58, I get no password match, as $password_to_check is different from the one stored in the database. In example: $password_to_check shows "ab2vG8KakAAGY" and the stored one is "abFcR2QZ/2fUU". What could be causing this? How should I compare the passwords? Thank you, Edo