ID3v1 tags with .m4a

I have a bunch of .m4a files encoded with Nero that have ID3v1 tags. I know this is non-standard, but this is the format Nokia phones use. mp3tag does not pick up these ID3v1 tags because as I understand it, mp3tag only looks for itunes style tags with .m4a files. In order to edit the tags I therefore have to change the file extension to .aac, then I change it back to .m4a again.

Is there any way to force mp3tag to pick up and edit ID3v1 tags in .m4a files?