This plugin provides configuration by convention rather than XML files and has several nice features like annotation mappings for methods and reasonable default mappings. Nice plugin overall but somehow it didn't wanted to work with Jetty. It was finding JSP files without problems, but totally ignored my Actions.
I had this error:
There is no Action mapped for namespace / and action name ########. - [unknown location] at com.opensymphony.xwork2.DefaultActionProxy.prepare(DefaultActionProxy.java:178) at org.apache.struts2.impl.StrutsActionProxy.prepare(StrutsActionProxy.java:61) ...
After experimenting for some time, I found that there is some mess with Jetty class loaders and to solve it there is nice configuration property for plugin itself. If you have the same issue you can fix it by adding
<constant name="struts.convention.exclude.parentClassLoader" value="false" />
to your struts.xml file.
Ironically, good old configuration solved convention plugin issues.