There is an incompatibility of the version of asm.jar library, The next commands adds a distinct version of asm.jar:
roma add persistence-jpox -> Add asm-3.1.jar
roma add services-cxf -> Add asm-2.2.3.jar
After executing this commands the two jars are in /lib folder and the web application catches the classes of the first one "asm-2.2.3.jar" (alphabetical order) and the ant task "Persistence Compile" fails because use the modern version "asm-3.1.jar"
I removed the old version (asm-2.2.3.jar) and leave only asm-3.1.jar and my application works fine with persistence and web services.
Maybe if you update the jar used by services-cxf, the bug can be fixed.