Mailing list archives (i.e., the compilation of the messages posted up-to-now) are often published on the web and indexed by conventional search engines. They store a vast knowledge capital. However, the ability to automatically recognize and process the information is mostly lost at publishing time. As a result, the current mailing list archives are difficult to query and have a limited use. This paper describes an usage of the Semantic Web technologies in order to avoid the information loss and to allow new applications to exploit the information in a more powerful way.