keep comments when "Submit different answer" by students

Hi

When a student update the answer ("Submit different answer") the comment done in the previous answer is removed together with the comment.

So for CPpro would like to keep the updates on the comments chronological.
Either :
1. integrate or open up custom type with advanced fields like plugins
of
2. integrate this by manual add more comments fields/feedback fields with date/time/subject etc etc

Regards Valentijn