Postfix + SASL + PAM + MySQL

Hi all!

First, my english is very bad. Sorry.

I'm trying to setup a Postfix which use a MySQL table to validate users.
I have a problem with SASL (version 2): If I don't use PAM, passwords in
MySQL can't be encrypted (with password() or crypt() functions), because
SASL2 only supports passwords in cleartext.

Therefore, my /etc/postfix/sasl/smtpd.conf is:

VaLKyRia:~# cat /etc/postfix/sasl/smtpd.conf
pwcheck_method: PAM

and my /etc/pam.d/smtp:

VaLKyRia:~# cat /etc/pam.d/smtp
#smtp
auth optional pam_mysql.so host=localhost db=postfix user=mail
passwd=my_passwd table=users usercolumn=id passwdcolumn=passwd crypt=2
account required pam_mysql.so host=localhost db=postfix user=mail
passwd=my_passwd table=users usercolumn=id passwdcolumn=passwd crypt=2

However, when I try to send a mail, I obtain into /var/log/mail.log this
error message:

VaLKyRia postfix/smtpd[3399]: warning: SASL authentication problem: unknown
password verifier

Why? Lots of documents say this is the correct way, althought
http://asg.web.cmu.edu/cyrus/download/sasl/options.html sais nothing about
that option.

I use Debian Sid. Installed packages:

VaLKyRia:~# dpkg -l | grep sasl ; dpkg -l | grep pam ; dpkg -l | grep
postfix
pi libsasl2 2.1.15-4 Authentication abstraction library
ii libsasl2-dev 2.1.15-4 Development files for authentication
abstrac
ii libsasl2-modul 2.1.15-4 Pluggable Authentication Modules for SASL
ii libsasl2-modul 2.1.15-4 Pluggable Authentication Modules for SASL
ii libsasl7 1.5.28-6 Authentication abstraction library
ii sasl-bin 1.5.28-6 Programs for manipulating the SASL users
dat
ii sasl2-bin 2.1.15-4 Programs for manipulating the SASL users
dat
ii libpam-modules 0.76-13 Pluggable Authentication Modules for PAM
ii libpam-mysql 0.5.0-2 PAM module allowing authentication from a
My
ii libpam-runtime 0.76-13 Runtime support for the PAM library
ii libpam0g 0.76-13 Pluggable Authentication Modules library
ii postfix 2.0.13-2 A high-performance mail transport agent
ii postfix-mysql 2.0.13-2 MYSQL map support for Postfix
ii postfix-tls 2.0.13-2 TLS and SASL support for Postfix

Thanks!