[Flac] metaflac: malformed vorbis comment field field contains no '=' character

[scar]

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hi all,

i have several flac files which have their comment tag filled up with...
comments, as well as the other tags filled in with relevant information.

and then i have some similar flac files, resulting from some audio
processing on the original flac files, in a subdirectory, S, for example.

i am using metaflac 1.2.1-1.2 on ubuntu 9.04 and i am running this
command in order to transfer the tags to the processed files:

metaflac --export-tags-to=- track1.flac | metaflac --import-tags-from=-
S/track1.flac

and then i proceed with track2.flac, track3.flac, etc.

on some of the files, i am receiving this error:

- -: ERROR: malformed vorbis comment field "<part of the comment>",
       field contains no '=' character


and thus none of the tags are transferred.  i put an equals sign into
the comment and then metaflac doesn't complain anymore.  however, on the
files that it did not complain about there was no equals sign in the
comments.  so i am confused as to what is the real problem.
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iEYEAREIAAYFAks70XIACgkQXhfCJNu98qBF0QCg6cWrFdEJvMknvxEnMbXKPaZh
CVYAniGrbDGD2Ja4bi8v8i0qd2LikOgT
=hf8U
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