  This paper has been withdrawn by the author. Instead, more comprehensive and
accurate works are placed in: 1) cond-mat/0610767: Universality in nonadiabatic
behaviour of classical actions in nonlinear models with separatrix crossings,
to appear in Phys.Rev.E; and 2) nlin/0611007: Change in the adiabatic invariant
in a nonlinear two-mode model of Feshbach resonance passage, to appear in
Physica D
