This isn't a new fix and I don't take any credit for it. It seems not to be widely known; I hope reposting it here will reduce the number of cries for help.
Airmon-ng doesn't work with certain NICs, especially newer Intel. It displays:
Interface Chipset Driver
and then hangs.
Background (optional extra)
In the version that ships with BT5R1, airmon-ng gets stuck in a "while" loop looking for the correct chipset. It tries to find the word "Link" in string "iwlagn 0000:04:00.0: Detected Intel(R) Centrino(R) Advanced-N 6230 AGN, REV=0xB" - not present therefore infinite loop. This was fixed by the aircrack team in r1972.
"Svn up" merely updates the source files in /pentest/wireless/aircrack-ng. "Make" etc is necessary to place the binaries in the path at /usr/local/sbin