Is it possible in Tomcat to allow running all servlets from a directory without configuring each one in web.xml ?

Jarek,
 maybe you can just use the same logic that is used by the servlet, calling an invoker for the given directory. I never tested it, but it sound right:

    <servlet>
        <servlet-name>
            invoker
        </servlet-name>
        <servlet-class>
            org.apache.tomcat.servlets.InvokerServlet
        </servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>
            invoker
        </servlet-name>
        <url-pattern>
            /myDirectory/*
        </url-pattern>
    </servlet-mapping>