Longest pre-credit sequence in a film

Before the opening title of Dennis Hopper's The Last Movie (US 1971), the pre-credits run for 30 minutes.  The cast alone was made up of 59 speaking roles, some of which were played by Peter Fonda, Dean Stockwell, Kris Kristofferson and Russ Tamblyn. 

Prior to this, the opening sequence to the James Bond film  On Her Majesty's Service (UK 1969) was the longest at approximatley sixteen minutes before the credits rolled.