Multi rename error - with some JPG images

[Dreamer]

- rename some image files containing EXIF date using [exif_taken] as name
- select two or more files with EXIF, but without date and time* - or any JPG files with EXIF
- press F2 to open multi rename window
= same TWO error messages appear:

"Invalid argument to date encode"

* Those files are probably not OK, they are from old Nikon camera (COOLPIX L4), other image programs show just 00.00.0000 as date and time.

If you need a sample, please let me know.

Edit: so it's not just that camera, also with Olympus FE4000,X920,X925, with the correct date and time in EXIF, it's OK with some images from the same camera, the problem is just with the few images - they look the same - size, resolution..