Choreographies offer means to describe the long-running collaboration of business partners. Such descriptions can be used to create new participant processes which comply to the overall choreography or to check whether participating processes conform to the protocol. In addition, choreography descriptions allow for asserting whether a completed cross-organizational conversation has been compliant to the planned choreography. However, choreography descriptions have so far not been used during execution but only during design time. Therefore, it is not yet possible to immediately detect protocol violations and to instantly handle such violations. In this paper we motivate the need of a Choreography-aware Service Bus which is capable of tracking the soundness of cross-organizational conversations while they are running. This fosters a novel notion of exception handling in the context of choreographies.