  Using a simple model of multi-band superconductors, which can be applied in
particular to Fe\nobreakdash-based pnictides, we calculate the Josephson
current $I_{\text{J}}$ in a tunnel junction composed by such superconductors.
We employ the tunneling Hamiltonian method and quasiclassical Green's
functions. We study both the case of coexistence of the superconducting
($\Delta $) and magnetic (SDW---spin density wave) order parameters and the
case when only the superconducting order parameter exists. We show that the
current $I_{\text{J}}$ depends on the mutual orientation of magnetization of
the SDW in the case of non-ideal nesting when the coexistence of
superconducting and magnetic order parameters is possible as it takes place in
Fe\nobreakdash-based pnictides. It is found that the realization of the
$\pi$\nobreakdash-junction is possible in both cases. We compare our results
for multi-band superconductors without the SDW with those obtained earlier and
find that they coincide if the tunneling matrix elements are real. If these
elements are complex, a new term appears in the formula for the Josephson
critical current.
