In the recent years a generalization of the harmonic oscillator using a complex deformation was investigated, where epsilon is a real parameter. Here, we will consider the most simple case: even and x real. We will give a complete characterization of three different classes of operators associated with the differential expression H: The class of all self-adjoint (Hermitian) operators, the class of all PT symmetric operators and the class of all P-self-adjoint operators. Surprisingly, some of the PT symmetric operators associated to this expression have no resolvent set.