H2 Hummer's Bose Stereo Auxillary Input

[TheGoodHummerMan]

I want to connect a portable MP3 player into my new H2 stereo which has the in-dash 6-disc CD changer. I see where the adapters by companies such as PIE specifically exclude this stereo for use with their adapters. However, I noticed that on the stereo itself, there is a toggle-button for CD/Aux. Has anyone removed this stereo and checked to see if by any chance there already are auxilliary inputs? If not, what IS the purpose of this button? Seems like an indication that an auxilliary device could be used with the unit?