Video conferencing software 2(+drivers)

I have a Gateway 700XL XP home w/media suite and w/business suite. Also Pinnacle Studio Version 8 SE software. I want to use my Sony DCR-TRV720 (NTSC)Digital Handycam as a video webcam for (live realtime)video on MSN Instant Messenger Video Conferencing.With all the $$ I have spent to link these two pieces of hardware, I still have yet to find the software/driver to make this work. Sony techs almost had a solution by phone,but cutoff. Called next Sony tech,said “No way camcorders can be used as webcams” WHY? I need it done w/o buying a cheap 300 pixel A/V webcam; BUT using hardware I have