[NTG-context] incorrect size of the font bounding box with MkIV

Hi Hans, I tried to get the boundry of Chinese punctuation in the scrp-cjk.lua file. Such as the bounding box information of Chinese comma in the AdobeSongStd-Light.otf font: bbox[1] = 36, bbox[2] = -78, bbox[3] = 963, bbox[4] = 833 However I got the following result with luatex + plain bbox[1] = 171, bbox[2] = -58, bbox[3] = 370, bbox[4] = 240 The latter is right. What's the reason for it? -- Best regards, Li Yanrui