Just experimenting with the various forum features. It is now unlocked.
Members who start a topic now have the option to either lock/unlock or delete that topic. You can only do so for topics you start. You can do so by clicking on the Topic Moderation link at the top of the page and selecting the options.
There may be times when you want to either lock a topic (just providing information and don't want any comments), or delete a topic because it out of date, you made a mistake, etc.
This option is now available.
Russell