500 Servlet Exception

/opt/resin//conf/resin-scuole.conf:16: com.caucho.server.webapp.WebApp.addServletMapping():
`main' is an unknown servlet-name.  servlet-mapping requires that the named
servlet be defined in a <servlet> configuration before the <servlet-mapping>.

14:       <servlet-mapping url-pattern="/js/*" servlet-name="resin-file"/>
15:       <servlet-mapping url-pattern="/image/*" servlet-name="resin-file"/>
16:       <servlet-mapping url-pattern="/" servlet-name="main"/>
17:       <session-config enable-cookies='false' enable-url-rewriting='true'/>
18:       <stderr-log path='${log.dir}/medicina-err.log' rollover-period='1W'
rollover-count='3'/>