  We propose a modified RKKY-technique to evaluate the magnetic properties of
the ferromagnetic Kondo-lattice model. Together with a previously developed
selfenergy approach to the conduction electron part of the model we get a
closed system of equations which can be solved self-consistently.
Ferromagnetism appears for relatively low electron (hole) densities, while it
is excluded around half-filling ($n=1$). For small $J$ conventional RKKY ($\sim
J^2$) is reproduced; however, with strong deviations already for very moderate
exchange couplings. For not too small $n$ a critical $J_c$ is needed to produce
ferromagnetism with a finite Curie temperature $T_{\textrm{C}}$, which
increases with $J$, then running into a kind of saturation, in order to fall
off again and disappearing above an upper critical exchange $J$.
