When replying to a post, a text similar to

As an answer to: Last night in town (!!) w. photos by Ralph at 10 Sep 2005 01:34:55:

sometimes preceeds the posting, but sometimes it doesn't. I have a couple of mlf forums, in some of them this header doesn't seem to appear at all.

How can I parameterize its appearance?

All the best,
Ralph
PS: I appreciate the support here, it's not a self-understood service!