Does it makes sense to use a single physical box in both DMZ and Secured Zone

Question

Hi,

I was sitting in a presentation where i was told it is ok to have a physical box (virtualized into two) where one resides in the DMZ zone and the other resides in the secured zone.

I found that such an approach smells bad.

Is there any production environment that uses such an approach. I don't have a lot of experience in this space (Virtualization) but i always believed that virtualization would always be used only in one zone (for e.g the Secured Zone)

Any ideas or thoughts?

Thanks, Manglu