  A search has been performed for scalar top quark pair production in the
lepton+jets channel in ~1 fb^(-1) of data. Kinematic differences between the
exotic stop-stopbar and the dominant ttbar process are used to separate the two
possible contributions. For scalar top quark masses of 145-175 GeV and chargino
masses of 105-135 GeV we obtain upper cross section limits at 95% confidence
level for stop-stopbar production that are a factor of ~7-12 higher than
expected for the Minimal Supersymmetric Standard Model (MSSM).
