code: synchronized private void setLevelsOnExistingLoggers() {
          Enumeration<?> enm = props.keys();
          while (enm.hasMoreElements()) {
              String key = (String) enm.nextElement();
              if (!key.endsWith(".level")) {
                  // Not a level definition.
                  continue;
              }
              int ix = key.length() - 6;
              String name = key.substring(0, ix);
              Level level = getLevelProperty(key, null);
              if (level == null) {
                  System.err.println("Bad level value for property: " + key);
                  continue;
              }
              for (LoggerContext cx : contexts()) {
                  Logger l = cx.findLogger(name);
                  if (l == null) {
                      continue;
                  }
                  l.setLevel(level);
              }
          }
      }
docs: changed to apply any level settings to any pre-existing loggers.