[NTG-context] \setuplayout[location=duplex] not working? (probably since a year)

Hello there. I'm messing around with imposition schemas and I think I've hit a bug or a dropped feature (but documented in the printed manual). Minimal example: \setuppapersize[A5][A4] \setuplayout[location=duplex] \starttext \dorecurse{20}{ \input knuth } \stoptext As far as I can see, the duplex location is ignored, as the page is always put in the left corner. Am I doing something wrong? The behaviour is the same with the one-year-old ConTeXt from TeXlive2011. -- Marco