react-overlays: Unknown props when using Overlay

Using React 15.2.0 and react-overlays 0.6.4 results in the following Warning in the console while using the Overlay component.

warning.js?8a56:44 Warning: Unknown props `placement`, `arrowOffsetLeft`, `arrowOffsetTop`, `positionLeft`, `positionTop` on <div> tag. Remove these props from the element. For details, see https://fb.me/react-unknown-prop
    in div (created by Select)
    in Position (created by Overlay)
    in div (created by RootCloseWrapper)
    in RootCloseWrapper (created by Overlay)

Some code that shows how i use the Overlay component so that it is clear that my code isn’t sending down wierd props.

        <Overlay placement="bottom" show={open} rootClose container={this} onHide={this.handleHide} target={this.handleTarget}>
          <div className={styles.menu}>
            {children.map((child, index) => {
              return React.cloneElement(child, {
                active: selected == index,
                onClick: this.handleSelect,
              })
            })}
          </div>
        </Overlay>