  We present two measurements of the ttbar production cross section in
collisions of protons and antiprotons at sqrt{s}=1.96 TeV. We analyze a dataset
of 310+/-20 pb-1 collected with the CDF2 detector. In the first measurement, we
select events with six to eight jets, at least one of which having a displaced
secondary vertex, little or no missing transverse energy and optimized
kinematical criteria consistent with the ttbar all-hadronic decay channel. In
the second measurement, we select events with four or more jets, at least one
of which having a displaced secondary vertex, high missing transverse energy,
and optimized kinematical criteria consistent with the decay of ttbar to
tau+jets. The averaged ttbar production cross section, determined from six
different measurements using the CDF2 detector in the dilepton, lepton+jets and
all-hadronic decay channels, is also calculated to be sigma_ttbar=7.1+/-0.6
(stat)+/-0.7(syst)+/-0.4 (lumi) pb, in agreement with the prediction of the
standard model.
