Adding id3 tags to a .m4a files

Hi,
I'd like to know if it's possible to add an id3 tag into an .m4a file.
According the MP4 registration authority MP4 also allows the embedding of an ID3 tag.
Does this option exist in mp3tag ?

Thank you

It's not possible with Mp3tag.

Although it's probably not recommended and it would definitely make baby Jesus cry, you could rename the MP4 files to MP3, add the tags and then rename back to MP4. Just tried and it works, although Mp3tag was very slow when doing that. Guess the MP4 parser that is working behind the scenes doesn't like that.