NPE inside ReasonableSakaiServlet

[buckett]

We just had a exception from ReasonableSakaiServlet:

NullPointerException

java.lang.Class in isAssignableFrom at line -2
uk.ac.cam.caret.sakai.rsf.servlet.ReasonableSakaiServlet in service at line 70 (application)
javax.servlet.http.HttpServlet in service at line 729
org.apache.catalina.core.ApplicationFilterChain in internalDoFilter at line 269 (application)
org.apache.catalina.core.ApplicationFilterChain in doFilter at line 188 (application)
org.sakaiproject.util.RequestFilter in doFilter at line 669 (application)

it looks like:

      if (t instanceof UniversalRuntimeException) {
        UniversalRuntimeException ure = (UniversalRuntimeException) t;
        if (ForcibleException.class.isAssignableFrom(ure.getCategory())) { // Line 70
          throw (ure);
        }
      }

so I think that the category returned from the UniversalRuntimeException is null.