[NTG-context] movies no longer recognized?

This used to work: \defineoverlay[tannenberg][% {\externalfigure[tannenberg.jpg][width=\overlaywidth,height=\overlayheight]}] \hfill\framed[offset=0pt,strut=no,background={foreground,tannenberg}] {\externalfigure[% /Users/hans/Cryptografie/College-Movies/Tannenberg.mov] [width=1.33\makeupheight,height=\makeupheight] }\hfill\null Now the second \externalfigure makes ConTeXt hang. Because leaving out the .jpg suffix makes the first \externalfigure a hang, it might be possible ConTeXt (no longer?) recognizes a .mov, but .mp4 suffers the same. How can I update this to a working version again? Hans van der Meer