begin dbms_session.modify_package_state ( dbms_session.reinitialize ); end; 

RESET_STATE is an Oracle exclusive feature that automatically stops session states leaking from one application usage to another.
Setting the session state in a request leaves the session with the current state, meaning that subsequent usages of that session can use the session state that has been set. For example, when an application borrows and returns a connection to a connection pool, if the sessions state is not cleared, the next usages of that connection can see the session state set in previous requests. Leaving session state in a session after returning that session to a pool, opens a vulnerability for elicit use of session state that was set.

Consider pooled applications where multiple users share the same connection. Application states such as Local Application Context can be used to set application information such as routing numbers, account numbers, addresses, medical and health care details.

RESET_STATE is a very important database feature that enables your developers to rely on the session state being clean when a session is returned to a connection pool with request boundaries. This can be an Oracle connection pool or a custom connection pool with added request boundaries. RESET_STATE clears session states guaranteed by the Oracle database.

RESET_STATE also improves your protection when using Transparent Application Continuity (TAC), because the session state is clean at the beginning of a new request.
RESET_STATE supersedes RESET_PACKAGE.