Using jpeg-recompress with cmyk color system doesn't works

[abarre]

We detected that jpeg images in the CYMK color system were not supported by jpeg-recompress. However, mozjpeg seems to support this color system.

jpeg-recompress -Q --quality medium -m mpe -S disable ~/Desktop/3346470422995_patch.jpeg test.jpg
Unsupported color conversion request

I tried to use jpegoptim on the same image that also leverages on mozjpeg and jpegoptim correctly compresses the image.

I think that the right color system is not correctly detected by jpeg-recompress and thus jpeg-recompress doesn't correctly call mozjpeg methods.