[NTG-context] Synonyms and XML - HOWTO?

Hello, I'm trying to get the following to work: \definesynonyms[abbreviation][abbreviations][\infull] \defineXMLargument [abbrev] [short=,full=] {\expanded{\abbreviation{\XMLop{short}}{\XMLop{full}}}} \defineXMLargument [abbreviations] {\completelistofabbreviations} \starttext \startXMLdata <abbreviations/> Blabla short<abbrev short="short" full="slightly longer short"/>. \stopXMLdata \stoptext But I don't succeede: the synonym is not put out. Any ideas on what I'm screwing up? Joh