  Collider experiments have recently measured the production cross section of
hard jets separated by a rapidity gap as a function of transverse momentum and
gap size. We show that these measurements reveal the relative frequencies for
the production of rapidity gaps in quark-quark, quark-gluon and gluon-gluon
interactions. The results are at variance with the idea that the exchange of 2
gluons is a first order approximation for the mechanism producing colorless
states, i.e. the hard QCD Pomeron. They do qualitatively support the "soft
color" or "color evaporation" scheme developed in the context of bound-state
heavy quark production.
