use DBI;
$dsn = 'dbi::Sybase:MY_Sybase_DB';
$user = 'db_analyst';
$password = 'db_pass';
$dbh = DBI->connect($dsn,$user, $passwd);

##</code><code>##

Can't connect to data source My_Sybase_db, no database 
driver specified and DBI_DSN env var not se
t at U:\scripts\dbi_test1.pl line 5