  We investigate the electronic state and the superconductivity in the
5-orbital Hubbard model for iron pnictides by using the dynamical mean-field
theory in conjunction with the Eliashberg equation. The renormalization factor
exhibits significant orbital dependence resulting in the large change in the
band dispersion as observed in recent ARPES experiments. The critical
interactions towards the magnetic, orbital and superconducting instabilities
are suppressed as compared with those from the random phase approximation (RPA)
due to local correlation effects. Remarkably, the s++-pairing phase due to the
orbital fluctuation is largely expanded relative to the RPA result, while the
s+--pairing phase due to the magnetic fluctuation is reduced.
