  Results for four-, five-, and six-parton tree amplitudes for massive
quark-antiquark scattering with gluons are calculated using the recursion
relations of Britto, Cachazo, Feng, and Witten. The required diagrams are
generated using shifts of the momenta of a pair of massless legs to complex
values. Checks verifying the calculations are described, and a simple formula
for the shifted spinors of an internal gluon is presented.
