Debian Double Dutch Gnome?

[Mart van de Wege <mvdwege@wanadoo.nl>]

Hi Folks,

First off, apologies for the bad pun :)
A minor question: my computer is being used by a flatmate of mine. She is unfortunately not fluent in English, so I selected Dutch as language from the gdm language menu. Unfortunately, everything still keeps turning up English in Gnome. Going to a terminal and typing 'locale' gives me all environment variables set to 'nl_NL.ISO-8859-1', which is also generated by locale-gen. Bash shell messages are Dutch, but even fooling around with different settings Gnome refuses to switch, giving me a warning that the locale is not supported.
As my flatmate prefers Gnome over KDE (as do I) this is really bothersome. What am I doing wrong, or is there some bug in localization, and if the latter, how can I help?

TIA

Mart