Gimp uses (and sets when saving) the fields defined by the JPEG standard (the XDensity and YDensity fields)(and I just checked this by patching a JPEG with bogus values in these fields)(see attachment, which should show 336/288 DPI, you can also use it to check what CorelPaint sees).
It is possible that this information is also kept elsewhere (EXIF data) and that CorelPaint overlooks the fields from the JFIF fields.
It is possible that this information is also kept elsewhere (EXIF data) and that CorelPaint overlooks the fields from the JFIF fields.