>This isn't a Unix pitfall, it's a Debian pitfall.
And that is an example of why I do not run Debian any more: (1) it assumes that I have nothing better to do than learn all of the details of the Debian system and (2) as soon as some complication like this dots-in-filenames thing makes it into stable, it is very difficult to remove because most Debian maintainers consider it-might-break-existing-code a winning argument.