  A search is presented for gluinos decaying via the supersymmetric partner of
the top quark using events with two same-sign leptons, jets and missing
transverse momentum. The analysis is performed with 2.05 fb^-1 of integrated
luminosity from pp collisions at sqrt(s) = 7 TeV collected by the ATLAS
detector at the LHC. No excess beyond the Standard Model expectation is
observed and exclusion limits are derived for simplified models where the
gluino decays via the supersymmetric partner of the top quark and in the
MSUGRA/CMSSM framework. In those scenarios, gluino masses below 550 GeV are
excluded at 95% CL within the parameter space considered, significantly
extending the coverage with respect to existing limits. Depending on the model
parameters, gluino masses up to 750 GeV can also be excluded at 95% CL.
