Large-scale information processing applications must rapidly search through high volume streams of structured and unstructured textual data to locate useful information. Content-based messaging systems (CBMSs) provide a powerful technology platform for building such stream handling systems. CBMSs make it possible to efficiently execute queries on messages in streams to extract those that contain content of interest. In this paper, we describe efforts to augment an experimental CBMS with the ability to perform efficient free-text search operations. The design of the CBMS platform, based upon a Java Messaging Service, is described, and an empirical evaluation is presented to demonstrate the performance implications of a range of queries varying in complexity.