DBI:Sybase connect error

[vizzz]

I'm trying to log into a sql server 2005 express through perl using
DBI and DBD::Sybase module.
this is my freetds.conf file (located under /etc/freetds/freetds.conf)

[MyServer70]
        host = 10.0.2.12
        port = 1449
        tds version = 7.0

running this simple script:

#!/usr/bin/perl

use DBI ;
$user = 'test_user' ;
$passwd = 'aaa' ;

$dbh = DBI->connect('DBI:Sybase:server=MyServer70', $user, $passwd);

i get:
DBI connect('server=MyServer70','test_user',...) failed: (no error
string) at test2.pl line 8

but if i call:
tsql -S MyServer70 -U test_user -I /etc/freetds/freetds.conf
or
tsql -H 10.0.2.12 -p 1449 -U test_user

i can successfully connect on the DB.

where is my problem?

thanks Andrea