  We study in the BFKL approach the total hadronic cross section for the
collision of two virtual photons for energies in the range of LEP2 and in the
range of future linear colliders. The BFKL resummation is done at the
next-to-leading order in the BFKL Green's function; photon impact factors are
taken instead at the leading order, but with the inclusion of the subleading
terms required by invariance under changes of the renormalization scale and of
the BFKL scale s_0. We compare our results with previous estimates based on a
similar kind of approximation.
