It was just a matter of configuration of the maven plugin
<configuration> <scanIntervalSeconds>10</scanIntervalSeconds> <jettyXml>jetty/jetty.xml</jettyXml> <webApp> <extraClasspath>${basedir}/jetty/classpath</extraClasspath> </webApp> </configuration>
to add a classpath folder to Jetty, it needs the extraClasspath folder in the webApp tag.