Hidden files showing up in too many places.

[MHR <mhullrich gmail com>]

I noticed, I think when I installed CentOS 5.1 x86_64 (GNOME 2.16.0),
that most of the windows that show access to files (e.g., for saving a
file, or something to a file) are showing all the hidden files, and I
can't figure out how to turn this off.  Is there a global switch or
option someplace that I might have activated that would cause this?
It's impacting my Evolution, OOo and SeaMonkey, at least, and it
doesn't seem to happen on my work desktop, which is also running
CentOS but the 32-bit version.

Any help/info would be appreciated.

Thanks.

mhr