As we added the _system.vcx class library of the FCC in our apps, we use this function (sorry for the french in it):

*-----
function GetCommonFolder
*
*/CC/ Returns a system folder
*
lparameters lnFolderID

*/CC/ Constants for lnFolderID
* 2 "\\servername\users\username\Paramètres Windows\Menu Démarrer\Programmes"
* 5 "\\servername\users\username\Paramètres Windows\Mes documents"
* 6 "C:\Documents and Settings\username\Favoris"
* 7 "\\servername\users\username\Paramètres Windows\Menu Démarrer\Programmes\Démarrage"
* 8 "C:\Documents and Settings\username\Recent"
* 9 "C:\Documents and Settings\username\SendTo"
* 11 "\\servername\users\username\Paramètres Windows\Menu Démarrer"
* 13 "\\servername\users\username\Paramètres Windows\Mes documents\Ma musique"
* 14 "\\servername\users\username\Paramètres Windows\Mes documents\Mes vidéos"
* 16 "\\servername\users\username\Paramètres Windows\Bureau"
* 19 "C:\Documents and Settings\username\Voisinage réseau"
* 20 "C:\WINDOWS\Fonts"
* 21 "C:\Documents and Settings\username\Modèles"
* 22 "C:\Documents and Settings\All Users\Menu Démarrer"
* 23 "C:\Documents and Settings\All Users\Menu Démarrer\Programmes"
* 24 "C:\Documents and Settings\All Users\Menu Démarrer\Programmes\Démarrage"
* 25 "C:\Documents and Settings\All Users\Bureau"
* 26 "\\servername\users\username\Paramètres Windows\Application Data"
* 27 "C:\Documents and Settings\username\Voisinage d'impression"
* 28 "C:\Documents and Settings\username\Local Settings\Application Data"
* 31 "C:\Documents and Settings\All Users\Favoris"
* 32 "C:\Temp\Temporary Internet Files"
* 33 "C:\Documents and Settings\username\Cookies"
* 34 "C:\Documents and Settings\username\Local Settings\Historique"
* 35 "C:\Documents and Settings\All Users\Application Data"
* 36 "C:\WINDOWS"
* 37 "C:\WINDOWS\System32"
* 38 "C:\Program Files"
* 39 "\\servername\users\username\Paramètres Windows\Mes documents\Mes images"
* 40 "C:\Documents and Settings\username"
* 41 "C:\WINDOWS\System32"
* 43 "C:\Program Files\Fichiers communs"
* 45 "C:\Documents and Settings\All Users\Modèles"
* 46 "C:\Documents and Settings\All Users\Documents"
* 47 "C:\Documents and Settings\All Users\Menu Démarrer\Programmes\Outils d'administration"
* 48 "C:\Documents and Settings\username\Menu Démarrer\Programmes\Outils d'administration"
* 53 "C:\Documents and Settings\All Users\Documents\Ma musique"
* 54 "C:\Documents and Settings\All Users\Documents\Mes images"
* 55 "C:\Documents and Settings\All Users\Documents\Mes vidéos"
* 56 "C:\WINDOWS\resources"
* 57 "C:\WINDOWS\resources\040c"
* 59 "C:\Documents and Settings\username\Local Settings\Application Data\Microsoft\CD Burning"

#DEFINE CSIDL_FLAG_CREATE 0x8000
local lcSystemFolder, loCommonFolder
lcSystemFolder = ''

loCommonFolder = newobject('_commonfolder')
if vartype(loCommonFolder) = 'O'
lcSystemFolder = loCommonFolder.getFolder(lnFolderID, CSIDL_FLAG_CREATE)
release loCommonFolder
endif

return lcSystemFolder
*-----