code: public void setLrParam(boolean flag) {
  		if(isModifiable == ModifiableRule.NotModifiable) {
  			throw new IllegalArgumentException("lr param of the URI is not modifiable and must not be set by the application");
  		}
  		if (flag) {
  			getSipURI().setLrParam();
  			super.parameters.put(LR_PARAM, null);
  		} else {
  			getSipURI().removeParameter(LR_PARAM);
  			super.parameters.remove(LR_PARAM);
  		}
  	}
docs: /*
  (non-Javadoc)
  @see javax.servlet.sip.SipURI#setLrParam(boolean)