Option to Close Thread when Replying

[Freestyler]

Ok, this one's probably pretty easy to do, for those of us who know how to do it anyway (and that's not me !).

When you're replying (as an Admin only) to a Thread, you can tick a box (amongst the other boxes like 'Show Signature') to choose to Close the Thread just after you reply.

It'll be handy for when people make administration requests, like new Forums being made for Clans (it's a gaming Forum), and us Admins just post a Reply saying 'Done', and don't want any replies after that as they're unneccessary.

So instead of Replying, then scrolling down and choosing 'Open/Close Thread', it just closes the Thread when you Reply.

This possible?