The paper presents the new agent framework XJAF and its application on distributed library catalogues. The framework is based on the Java EE technology and uses the concept of the plug-ins for implementation of the basic framework components. One important plug-in of the agent framework has been introduced into this system: the inter-facilitator connection plug-in, which defines how multiple facilitators form an agent network. The inter-facilitator connection plug-in is particularly important in both design and implementation phases in the field of distributed library catalogues. In order to substantiate the above statement, the framework has been used for implementation of the agent-based central catalogue of the library information system BISIS. Also, the framework has been used to implement the agent-based metadata harvesting system for the networked digital library of theses and dissertations (NDLTD). Both systems have been implemented at the University of Novi Sad.