Anyway to make "Subject" field non-mandatory?

Anyway to make "Subject" field non-mandatory?

Hi,

I love ZOHO CRM! Keep up the great work!

Is there any way to make the Subject field in (say Sales Order, Event etc) non-mandatory? I do not understand th logic behind it. It's not a unique field. If it isn't a unique field, it is possible that after some time you'll end up with multiple records having the same Subject. In any case, why should a Subject be a mandatory field in a Sales Order or Invoice etc.? I have tried to turn this off but I can't. Am I missing something?

Thanks,
Kenneth