BuddyPress.org

Everyone needs to remember that many BP plugins break going from 1.1 to 1.2. This is a small price to pay for all the refactoring done but it means you’ll be better off moving all your old BP plugins out of the plugins folder before getting BP 1.2 smooth and then bring them back in 1 at a time.

Additionally, I have found it quite common that some ftp clients do an incomplete load and reloading the bp files again solves the problem (like @bbrian017’s undefined BP function errors)