How can I change (theme) the color of my objects in Object Mode? Heads-up: I'm not talking about assigning materials or matcap, ok?? I'd like to change the default color of objects when you startup blender with a raw scene or when you haven't assigned them materials and is (not) using matcap. :))

I've been trying to customize my interface in Blender but I haven't found an option to change the color of the object in Object mode. It stays that slightly purple/blueish and I can't change that. However, there is an oprtion for changing the object's color while in Edit mode, very customizable.

Does anyone know how can i customize the color of my object in Object Mode?
Object color in solid view is controlled by the lights in User Preferences > System: