When using the m-let service with the JDK 1.3 software, in particular when calling the method getMBeansFromURL(java.lang.String url) or getMBeansFromURL(java.net.URL url), a javax.management.ServiceNotFoundException is raised. This occurs because the JDK 1.3 APIs send HTTP/1.1 client requests and some HTTP server versions will reject all client requests that are not HTTP/1.0 or HTTP/0.9. Therefore, you need to ensure that your HTTP server accepts HTTP/1.1 client requests.