[PHP] Problem with mcrypt_encrypt and mcrypt_decrypt.

[francesco]

Hi all,
i'm trying to crypt and decrypt password with the code below but i get many warnings

Warning: mcrypt_get_iv_size(): Module initialization failed in 
/web/htdocs/www.automationsoft.biz/home/invio_mail.php on line 36

Warning: mcrypt_create_iv(): Can not create an IV with size 0 or smaller in 
/web/htdocs/www.automationsoft.biz/home/invio_mail.php on line 37

Warning: mcrypt_decrypt(): Module initialization failed in 
/web/htdocs/www.automationsoft.biz/home/invio_mail.php on line 38
 
and i don't understand why, any help is appreciated.
Code is below.

This code is in a script 
  //Start crypt
  $iv_size=mcrypt_get_iv_size(MCRYPT_BLOWFISH,MYCRYPT_MODE_CBC);
  $iv=mcrypt_create_iv($iv_size,MCRYPT_RAND);
  $key=genera();// genera() function for rand number
  $emailcifrata=mcrypt_encrypt(MCRYPT_BLOWFISH,$key,$email,MYCRYPT_MODE_CBC,$iv);
  $emailcifrata=$key.$emailcifrata;
  // End crypt
This code is in another script that isn't the same script of previous  
  //Start decrypt
  $emailcifrata=fgets($fp);
  $lunghezza_str=strlen($emailcifrata);
  $emailcifrata=substr($emailcifrata,10);
  $key=substr($emailcifrata,0,($lunghezza_str-10));
  $iv_size=mcrypt_get_iv_size(MCRYPT_BLOWFISH,MYCRYPT_MODE_CBC);
  $iv=mcrypt_create_iv($iv_size,MCRYPT_RAND);
  $email=mcrypt_decrypt(MCRYPT_BLOWFISH,$key,$email,MYCRYPT_MODE_CBC,$iv);
  // End decrypt

Thanks in advance.