by Luis de Vasconcelos.
Sorry, I'm not familiar with FreeTDS on UNIX... but what happens when you try to connect using the 'mssql' dbtype without a DSN:
$CFG->dbtype = 'mssql';
And what happens when you connect to the MSSQL instance using the syntax below:
$CFG->dbhost = 'servername/instancename'; (that might be a backslash, depending on your MSSQL config...)