Abstract
See paper for full list of authors - 8 pages, 4 postscript figures, submitted to Phys. Rev. D. RC; We have searched for the lepton-number violating processes B+ -> h- l+ l+ with h- = K-/pi- and l+ = e+/mu+, using a sample of 471+/-3 million BBbar events collected with the BaBar detector at the PEP-II e+e- collider at the SLAC National Accelerator Laboratory. We find no evidence for these decays and place 90% confidence level upper limits on their branching fractions Br(B+ -> pi- e+ e+) < 2.3 x 10^{-8}, Br(B+ -> K- e+ e+) < 3.0 x 10^{-8}, Br(B+ -> pi- mu+ mu+) < 10.7 x 10^{-8}, and Br(B+ -> K- mu+ mu+) < 6.7 x 10^{-8}.