metaflac --no-utf8-convert complains about UTF

This is 1.3.1 on OpenBSD/amd64.
The --no-utf8-convert option of metaflac(1) does not work for me:

$ metaflac --no-utf8-convert --set-tag=3D"Artist=3D=AEou=BEl=ED=E8ek" aladi=
n.flac
aladin.flac: ERROR: tag value for 'Artist' is not valid UTF-8
(You probably can't see the Czech letters properly in my mail,
but that's beside the point.)

Indeed, it is not valid UTF8 (it's LATIN2), but isn't metaflac
supposed to just write it as specified, with this option?

	Jan