The \"install\" goal copies the artifact to the target directory and to the local repository.
How can I tell Maven to copy it also to a given directory
The best approach would be to use a plugin which will actually deploy your application, such as cargo or jboss-maven plugin (credit to @Andreas_D for that one).
This would be a better approach to using a copy or generic upload tool since deploying is what you are actually trying to do.
With the cargo plugin you have the option to deploy to a variety of running servers. We took this approach to test locally in jetty using the jetty plugin during the build and had a profile to deploy to tomcat on demand via cargo.
Note: If you have your target server (JBOSS) installed locally on the dev box as well then you can also use cargo to start/stop your server during your build process as well. The downside of this approach is that you will need it to reference it's location in the pom file, so either all devs install it in the same location or a system property that defines where it is located (similar to JAVA_HOME).