Hi, i'm using zend server ce 5.6 SP4 with php 5.3.14 and zend framework 2.0.6 with a postgres database 9.1, i use the Authentication class using the example in the official documentation :

$adapter = new AuthAdapter($db,
'users',
'username',
'password',
"MD5(CONCAT('staticSalt', ?, password_salt))"
);

When i use it with mysql database it work fine, but with postgres i get this error:

SQLSTATE[42P18]: Indeterminate datatype: 7 ERROR: could not determine data type of parameter $1

When i change the CredentialTreatment from "MD5(CONCAT('staticSalt', ?, password_salt))" to "MD5(?)" it works fine, but when i change it to a simple "MD5(concat(?))" give me the same SQLSTATE error.