  We study some quantum systems described by noncanonical commutation relations
formally expressed as [q,p]=ihbar(I + chi H), where H is the associated
(harmonic oscillator-like) Hamiltonian of the system, and chi is a Hermitian
(constant) operator, i.e. [H,chi]=0 . In passing, we also consider a simple
(chi=0 canonical) model, in the framework of a relativistic Klein-Gordon-like
wave equation.
