I had this once on a transit van and the brake fluid had lost its viscosity, it just went one day, i replaced the brake fluid and it was fine, like JD said more info would help.
james, December 2009
Tell us a bit more please.
E.g. what are your air pressure gauges (on the dashboard in front of the driver) reading?
Was this on the road or during a DOE or MOT?
Was it complete brake failure or just on one side/ front or rear?