Typically when an application component requests a connection handle in the context of a transaction, the connection is automatically enlisted in the transaction. This occurs even if the connection is never used, which results in unnecessary overhead.
With lazy enlistment, a new connection is enlisted in the transaction only if it is actually used in the transaction; that is, only if data is transmitted through the connection.
Both a JMS resource adapter and a foreign application server must support lazy enlistment for this feature to be used in your application environment.