I've seen a warning on a parve product that backs this up.  Basically said
that while the product was milk-free and produced on a dedicated line,
milk was used elsewhere in the same plant, so there was a very low risk of
airborne cross-contamination.

Gail Lewis

On Tue, 15 Oct 2002, Grace V. Palazzolo wrote:

> You all may be interested in another opinion about relying hechshers
> for a dairy-free diet. When I read this, I nearly fell out of my
> chair. It's written by a Cornell professor (I live in Ithaca, NY).
>
> http://www.foodallergy.org/topics_archive/pareve.html
> --
>
> -- Grace
>