1. Method for dynamically integrating Backend System instances into a J2EE application server environment, comprising: deploying a J2C connector suitable for Backend System instances belonging to the same type of Backend Systems (A; B; C) into said J2EE application server environment by using a J2C deployment descriptor which does not contain properties for identifying and connecting to a Backend System instance (A 1 -A 3 ; B 1 -B 3 ; C 1 -C 3 ; access data); restarting said J2EE application server; detecting availability of Backend System instances (A 1 -A 3 ; B 1 -B 3 ; C 1 -C 3 ); determining access data to said Backend System instances; persistently storing said access data; reading said access data and passing them as a part of a request to said J2C connector (A; B; C) in any case an operation on the particular Backend System instance has to be performed; and automatically creating a connection with said particular Backend System instance by said J2C connector (A; B; C) at runtime without restarting said J2EE application server.