Please look at the attached file. There is a multi-module project, one module is a war, another is a Jar, containing a JUnit test that download a file served by the war. Jetty is started with such war in the jar module, before the test phase and by using the overlay mechanism (i.e., by listing the war as a dependency in the jar).
Everything works fine when I run 'mvn test' from the jar module. However, if I run the same maven command from the parent level (i.e., the pom-packaged project containing both modules), the test in the jar fails and it looks like the overlay is ignored.
Jetty plug-in 8.1.5.v20120716, 3.0.3 (r1075438; 2011-02-28 17:31:09+0000), Java 1.7.0_07, OS X 10.7.4