Done. I neither have a win machine, but when you plug in usb and select "pc-suite" mode obexd should be signaled. You could see it in the debug output. And a signaling should happen when unplugging usb.
Jul 18 20:49:09 Nokia-N900 obexd[1629]: plugins/usb.c:handle_io_signal() SIGUSR1 Jul 18 20:49:09 Nokia-N900 obexd[1629]: src/obex.c:obex_session_start() Jul 18 20:49:09 Nokia-N900 obexd[1629]: plugins/usb.c:usb_connect() Successfully opened /dev/ttyGS0 Jul 18 20:49:09 Nokia-N900 root: /usr/sbin/pcsuite-enable.sh: sent SIGUSR1 to obexd Jul 18 20:49:09 Nokia-N900 root: /usr/sbin/pcsuite-enable.sh: sent SIGUSR1 to syncd ... Jul 18 20:49:09 Nokia-N900 [1385]: GLIB DEBUG default - usb-plugin::current-state: PC Suite Mode