RK> Oops, that should be gapnamespace of course.
Ah, and the vital words
Parameters passed to a generator must be prefixed with a g. For instance, when using generator=backlinks, use gbltitle instead of bltitle.
are missing from e.g., http://www.mediawiki.org/w/api.php That's right, nowhere in it are the two worlds (g and non g) linked.
By the way, to generate the names of all the pages of a site, one needs some kind of recursive generation: for namespace in $(namespaces) do for page in $(pages namespace) dump $page I wonder if that is possible in a single URL.