Reply to Thread APPEARS to respond to the last poster, NOT the thread as a whole

[Bill Stuntz]

I've found the plugin, but I don't know where it came from. It works properly when replying to a specific post by using the correct non-zero parentid, but "Reply to Thread" seems to pick an inappropriate parentid. The first post's parentid=0 so no link is shown in the first post's title.

I'm just guessing here: If it set the parentid to 0 instead of the incorrect postid that it picks now when invoked by "Reply to Thread" it shouldn't display ANY link in that new post title - which is what I want. I see too many "What's he shouting at ME for? Somebody ELSE said that!" complaints when somebody does a "Reply to Thread" that unintentionally points to the wrong post. It shouldn't point to ANY post instead of pointing to a wrong one.

Trouble is, I can't FIND "Reply to Thread" or "Reply" [to post] to figure out exactly how they work, and hopefully inhibit the incorrect link for a "Reply to Thread" while allowing the correct links to display when they're responding to a specific post.

P.S. The link is actually displayed in the post title by the following lines in a modified postbit_legacy:

<vb:if condition="$post['parentid'] AND $post['parentusername']">
(RE: <a href="{vb:link thread, {vb:raw thread}, {vb:raw pageinfo_post}}#post{vb:raw post.parentid}">{vb:raw post.parentusername}</a>)
</vb:if>

If parentid=0, the condition fails, and no link is displayed.