[KevinL]

Use different prefixes Right above the lines you posted:

	// ******** DATASTORE PREFIX ******
	// If you are using a PHP Caching system (APC, XCache, eAccelerator) with more
	// than one set of forums installed on your host, you *may* need to use a prefix
	// so that they do not try to use the same variable within the cache.
	// This works in a similar manner to the database table prefix.
// $config['Datastore']['prefix'] = '';