long field atoms for m4a

Hello,

I understand m4a using atoms to store its tags. They are limited to 255 characters. But ©lyr is the only field that doesn't fall under this category.

I want to store long information, but not into lyrics. Could mp3tag, please implement a field maybe "©cml": comment long, which doesn't fall under the 255 character limit.

This will very useful to store the information into this field.

Thanks,
Rajanna