  We reconsider the calculation of a non-global QCD observable and find the
possible breakdown of QCD coherence. This breakdown arises as a result of wide
angle soft gluon emission developing a sensitivity to emission at small angles
and it leads to the appearance of super-leading logarithms. We use the `gaps
between jets' cross-section as a concrete example and illustrate that the new
logarithms are intimately connected with the presence of Coulomb gluon
contributions. Numerical estimates of their potential phenomenological
significance are presented.
