Transparency refraction changes if object is in a symbol?

[SamIWas]

I've been working on some lighting fixtures with glass lenses.  I got the lenses looking really nice with some glass refraction.  But since I'm using so many of them, I decided to make the individual lens a 3D symbol.  So, I selected one of the lenses and made it a symbol.  But, the symbol will not take on the same nice refractive properties of the individual meshes.  The mesh inside the symbol is the exact same as the meshes not inside the symbol.  Same rendering settings, same everything.  It's literally a copy/paste.  But the refraction does not work.  Look at the center lens on the fixture...that one is the symbol while the rest are individual meshes.  It just renders white.  

 

The texture is a grey color, with a glass reflection, and glass transparency with 1.8 refraction.  

 

Any ideas?