  We have measured the conductivity in a gated high-mobility GaAs two
dimensional hole sample with densities in the range (7-17)x10^9 cm^-2 and at
hole temperatures down to 5x10^-3 E_F. We measure the weak localization
corrections to the conductivity g=G/(e^2/h) as a function of magnetic field
(Delta g=0.019 +/- 0.006 at g=1.5 and T=9 mK) and temperature (d ln g/dT<0.0058
and 0.0084 at g=1.56 and 2.8). These values are less than a few percent of the
value 1/pi predicted by standard weak localization theory for a disordered 2D
Fermi liquid
