t --> W+ b and t --> H+ b at the quantum level in the MSSM

We compare the standard top quark decay and the charged Higgs decay of the top quark, t --> W+ b and t --> H+ b, at the quantum level in the MSSM. While the SUSY loop corrections to the standard top quark decay are only of a few percent, it turns out that t --> H+ b is a most promising candidate for carrying large quantum SUSY signatures. As a result, the (tan(beta), M_{H±}) exclusion plots presented by the CDF Collaboration should be thoroughly revised in the light of the MSSM.