ReduxRouter does not remove hashchange-listener on unmount

When unmounting an React-app with ReactDOM.unmountComponentAtNode() the hashchange-listener of createHistory is not removed. It is added by the history.listen call in client.js, but the returned unlisten-function is not stored and never called.
Somehow the unlisten function needs to get called in ReduxRouter.componentWillUnmount().

As a quickfix, I added the unlisten-function to the returned store of historySynchronization() and called it from ReduxRouter.componentWillUnmount, but I guess thats not the best way to do it...

Thx for your help!