  In this short note we discuss the origin of spikes in physical distributions
in dijet production, originating after the Monte Carlo shower of POWHEG Les
Houches events. We introduce a refinement of the way in which the POWHEG BOX
separates the singular regions that reduces the appearance of spikes in the
computed distributions. We also study the sensitivity of the results due to a
modification of the way the POWHEG events are passed to the shower Monte Carlo
program. We recommend that the new features should be used always in dijet
production.
