FWIW - I'm not a FCD user ;-)
Getting this on a ubuntu 10.10 box trying to compile gr 3.7.1
Linking CXX executable fcd_nfm_rx
../../lib/libgnuradio-fcd-3.7.1.so.0.0.0: undefined reference to `libusb_handle_events_completed'
collect2: ld returned 1 exit status
make[2]: *** [gr-fcd/examples/c++/fcd_nfm_rx] Error 1
make[1]: *** [gr-fcd/examples/c++/CMakeFiles/fcd_nfm_rx.dir/all] Error 2
make: *** [all] Error 2
Max