I would like to be able to edit / change the Subject lines of received e-mails.

I followed the thread here              but although this technique succeeds in altering the subject line, it gives the e-mail a new "received" date and time.

I need to rename messages marked as Spam that I do not check every day and other messages received some time ago.

Is there a way to edit the Subject line of received e-mails without changing any of the other message headers?

Is this a feature I have missed, or will this feature be added in the near future?

Regards,