If we export 'fractions' and 'contrMat' R CMD check tells us to document them. Therefore we prefer to call them via MASS::fractions and multcomp:::contrMat.
NEWS: Moved MASS, PolynomF, multcomp, lattice, mvtnorm, Matrix, CommonJavaJars and methods from DEPENDS to IMPORTS. Therefore loading gMCP will no longer add these packages to the search path and if for example you want to use contrMat you have to load/attach the package yourself.