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 > I am not Jewish, so I'm certainly not an authority on what's kosher and
 > what isn't.  I agree that most Jews' definitions of chometz and kosher
 > for passover are not synonymous with "gluten free."  However, the authors
 > of the Kollel guide specifically say that "any foods that
 > contain ingredients derived from any of the following grains:  wheat,
 > barley, oats, rye, or spelt involve Passover Kashrus issues.

I think you are interpreting this paragraph wrong.

To me, it says:
if it does not have any of these grains, there is no passover kashrut issue.
If it does have any of these grains, there is an issue.  What they mean,
though, when they say there is an issues is:
when the grains are present, they must have been grown, stored, and prepared
according to jewish law.

If any grains present were certified as prepared according to the rules, it
is considered kosher for passover. (But obviously NOT gluten free)

By the way, the storage and preparation rules have to do with making sure
that the grains have not come in contact with moisture, because that may have
allowed a fermentation process to begin.  Likewise, they must be baked for less
than some specified time limit, so that the grain does not have a chance to
 rise.

What makes something not kosher for passover is that it contains, or might
contain, fermented grain.

Don't feel bad if this is confusing.  This is all confusing to me also,
and I went to rabbinic school for 3 years.

-Ric