The PowerBook ZoomedVideo file is a system extension that enhances system stability on PowerBook 3400 series, PowerBook 2400/180, and PowerBook G3 computers when running video conferencing applications using the Zoomed Video port. It also fixes compatibility problems with CU-SeeMe(R) version 3.1 and iVisit(TM) 1.0 (http://www.ivisit.com and http://www.cuseeme.com).