  The D0 meson can decay to the wrong sign K+pi- state either through a doubly
Cabibbo suppressed decay or via mixing to the D0bar state followed by the
Cabibbo favoured decay D0bar -> K+ pi-. We measure the rate of wrong sign
decays relative to the Cabibbo favoured decay to (0.383 +- 0.044 +- 0.022)% and
give our sensitivity to a mixing signal.
