I knew that, infact i should use ( as i do ) BookShop/OperazioniUtenti/remote ( BookShop is a .jar inside my web project, i don't have yet a .war nor a .ear ). I don't get errors from the compiler but only at run-time.
...and i use the remote access because....i'm totally new with all jboss, java, ejb, jsp, servlet and i totally copying from tutorial and similar projects of my friends...so i'm not sure of what i do and if i do it the right way...