  We consider a long superconductor-ferromagnet-superconductor junction with
one spin-active region. It is shown that an \textit{odd} number of Cooper pairs
cannot have a long-range propagation when there is \textit{only one}
spin-active region. When temperature is much lower than the Thouless energy,
the coherent transport of \textit{two} Cooper pairs becomes dominant process
and the \textit{superharmonic} current-phase relation is obtained
($I\propto\sin2\phi$).
