  GR@PPA 2.8 is a program package including event generators for single and
double weak-boson production processes at hadron collisions, in which a jet
matching method is implemented for simulating the weak-boson kinematics in the
entire phase space. Since the initial release in November, 2010, several
improvements have been applied to the program components. This report describes
the improvements and changes applied so far, up to the 2.8.3 release.
