Leading Zero in Track Numbers For mp4

Does this not work for if you want to lable m4a.

When I try to lable the mp3 I can change the track number from

Track 3 to Track 03

But if I pull up the m4a files, I cannot change it so it has a leading zero.

Is this just the way m4a files work? Or is it something I am doing wrong

Thanks and thanks for having an excellent program, it's the best I've seen so far.

The m4a tagging format does not support leading zeroes.