JetViP 2.1: the hbook version

Abstract We present an update of the JetViP 1.1 program for performing fixed NLO calculations in jet production including direct and resolved components in a continuous range of photon virtuality Q 2 . The new version allows to access the full event record on the parton level. The program is set up such that hbook can be used to fill histograms. The phase space generator has been optimized and the azimuthal dependence of the cross sections is taken into account in LO. We comment on recent comparisons between various NLO programs for jet production at HERA. We demonstrate that the ∑ E T cut for dijet cross sections is not infrared safe.