Thread:Project:Support desk/Importing from one mediawiki to another - help/reply

Well, at first look it seems that you should also import Template:ForumNewPost and Template:ForumReplyPost from the original wiki.

Also, if it uses a forum extension, and the messages are stored in it's own page (internally), each forum thread will be split with each message in a different page. That's the job of the forum extension, and you won't be able to emulate that, unless you manually create pages for each thread and transclude the contents of each message there.