Any idea what replaced the Active field in the forum table?

[sel100]

We are currently running vbulletin version 2.3.0 and are in the process of upgrading to 3.0.3. There are obviously changes in the database table structure and somewhere from version 2.3.0 to version 3 one of those changes appear to be the active field in the forum table. This field appears to have been dropped in one of the versions along the upgrade route to the latest current version, does anyone know if it has been replaced with something else? Our problem is how to get the current number of active threads from the Mysql database? The reason we need this information is that it is displayed on our home page using a script which no longer works with version 3.0.3 because of this change.
Many thanks,
Sel