Enable Netbeans 8.01 to allow generation of session beans from entity classes

HI, I am using Netbeans 8.0.1 in FreeBSD 10., with jdk 1.7 and maven running in the environment. When I come to generate session beans from entity classes, the Next button on the New Session Beans for Entity Classes is disabled. And there is a Red warnning message stated "The project does not have the target server set properly. Java Persistence features are server-dependent". I have added Jboss 7.2 in the Tool->Servers setup, however, it still shown the errors and the I can't proceed to generate Session beans because Next button is disabled. Any help is highly appreciated. Thanks