A measurement of the top-quark mass is presented using Tevatron data from proton-antiproton collisions at center-of-mass energy $sqrt{s}=1.96$ TeV collected with the CDF II detector. Events are selected from a sample of candidates for production of $
tbar t$ pairs that decay into the lepton+jets channel. The top-quark mass is measured with an unbinned maximum likelihood method where the event probability density functions are calculated using signal and background matrix elements, as well as a set of parameterized jet-to-parton transfer functions. The likelihood function is maximized with respect to the top-quark mass, the signal fraction in the sample, and a correction to the jet energy scale (JES) calibration of the calorimeter jets. The simultaneous measurement of the JES correction ($JES$) amounts to an additional textit{in situ} jet energy calibration based on the known mass of the hadronically decaying $W$ boson. Using the data sample of 578 lepton+jets candidate events, corresponding to 3.2 $fb^{-1}$ of integrated luminosity, the top-quark mass is measured to be $m_t = rm 172.4 pm 1.4:(stat+JES) pm 1.3:(syst) GeV/{it c}^2$.
