>  I'm just
> asking if it's the general media where you heard this or where you may
> have
> read it.

Being suspicious of third-hand information is entirely appropriate, so why
aren't you googling for this yourself in order to eliminate as many
middlemen as possible?  My first stab at a search returned several fairly
authoritative references in the first few pages of hits:

http://www.google.com/search?hl=en&q=%22Vitamin+D%22+ultraviolet+glass&btnG=Google+Search