public Principal authenticate(String username, Object credentials, Request request) {

			if (credentials instanceof String) {
				Principal p = CommunityDAO.get().authenticate(username, (String) credentials);
				if( logger.isLoggable(Level.FINER) ) {
					logger.finer("OurHashRealm authenticate(), got principal: " + p);
				}
				return p;
			} else {
				if( credentials != null ) {
					logger.warning("Got authenticate call, but credentials is not a string. Instead; " + credentials.getClass().getCanonicalName() + " (user: " + username + ")" );
				} else {
					logger.warning("Authenticate called with null credentials for user: " + username);
				}
			}
			return null;
		}