A transformation of the linear second-order Fokker-Planck equations oc
curring in quantum optics is presented which overcomes difficulties co
nnected with negative definiteness of the diffusion matrices. This tra
nsformation is based on a dynamical ordering of quantum quasiprobabili
ty distribution functions. The ordering depends on the parameters of t
he dynamical problem under consideration. An algorithm leading to exac
t solutions of the dynamically ordered Fokker-Planck equations with ar
bitrary initial conditions is given, and simple criteria, how to recog
nize squeezed light in arbitrary ordering, are presented. The problem
of Fokker-Planck equations with time-dependent diffusion is also inves
tigated.