[dev-context] \setuppapersize: mirrored, negative, rotated, etc. not working in mkiv

Hi, While working on the wiki I discovered that mkiv fails on a few \setuppapersizes keys. Minimal example below. I'm using mkiv, 2012.04.19 23:18. mkii does it all with no problems. I discovered this while working out what the various keys do; I myself don't need a fix. --Sietse % negative causes an 'undefined control sequence' error. % So do mirrored, 90, 180, and 270. % rotated causes no error, but does nothing % \setuppapersize[A6][A5] % works \setuppapersize[A6,negative][A5] %fails \starttext asdf \stoptext