We study gauge mediation of supersymmetry breaking in SU(5) supersymmetric grand unified theory with gauge fields as messengers. The generated soft supersymmetry breaking parameters lead to close to maximal mixing scenario for the Higgs mass and highly red
neglectingtermsproportionaltoAtinEqs.(2.5)and
(2.3)
we
nd
that
a
typical
stop
mixing
is
At
ExtremelylargeAtinthecaseofthesamesignasM3contributessigni cantlytotherunningofmt andconsequentlytotherunningofmHu.Therefore,At mt mHu MZisrequiredandtheEWscaleisaresultoflargecancelations.2