i dont remember if there's such option in yabb 1g
if you sort the message index based on the topic's posted date, the problem is: when someone replied to a topic in the 2nd or 3rd page, others won't notice, and what about if someone replied to a topic in page 10? no one will read that, unless if your users browse all of the pages to find new topics
QuoteThis puts them up at the top of the list and many people have already viewed the message several times.
wouldn't your member like to view the new post?
they can click on the [new] button and it will redirect them to the last post that they read in a topic
if u still want to do this though, its still possible to code