getting analog switch common mode down to -0.10V

Hi

I need the ADG709 input to go 1/10V below ground, so ourplan is to use a diode as a shunt regulator on V- (-15V at 10KOhm bias). The V+ supply pin is at 5V. Is this a viable approach? What are the pitfalls? See attached.

Thanks

-Tim Starr on behalf of AK.G