OK - so that means that DBD::Sybase is trying to open a new connection. Is that done on purpose?

If that's NOT the case then you should make sure that any $sth really go out of scope or are cleaned up before executing the next call. Maybe consider using the syb_no_child_con option to make sure that DBD::Sybase doesn't attempt to open a second connection if there is already an "active" statement handle on the current $dbh.

Michael