code: protected synchronized void createTarget(Servlet s) throws InjectionException{ //596191
          if (s instanceof SingleThreadModel) {
              isSTM = true;
              servletConfig.setSingleThreadModelServlet(isSTM);
              target = new SingleThreadModelServlet(s.getClass());
          } else {
              target = s;
          }
      }
docs: WAS.webcontainer