Sorting index (in Spanish)

[Mari Voipio <mari.voipio@iki.fi>]

Dear Fellow-Contexters,

I have been charged with editing a ConTeXt document in Spanish (of which 
I understand preciously little). This far I have gotten over the hurdles 
of hyphenation, labeltexts and the upside-down exclamation mark (and as 
far as we can tell, the Spanish hyphenation patterns get loaded, too), 
but now I have a problem sorting the index: the words 'ángulo' and 
'índice' get sorted in the beginning of the index instead of among a and i.

It tried putting something like the example below in a) the setup part 
of my document, b) just before the index (a bit like in the example at 
<http://www.ntg.nl/pipermail/ntg-context/2005/008346.html>, except that 
I use the command \placeindex and not \completeindex) and c) in the 
lang-ita.tex file.

% Changes to sorting to fix the sorting of accented letters
\startlanguagespecifics[es]
\definesortkey {\´a}{a}{a}{\´a}  % á sorted among 'a'
\definesortkey {\´i}{i}{i}{\´i}  % í sorted among 'i'
\stoplanguagespecifics

None of the options a)-c) worked and I'm thinking that this is more of a 
  "stupid user" problem, i.e. as I cannot find any description on how 
\definesortkey works, I just don't understand how to use it properly.


Any help???

Mari


PS. Tried to find related info in contextgarden.net, but can't find much 
  - if it isn't there, I can add stuff (*after* I solve this problem) if 
somebody tells me where I may start growing this flower of mine.