  Recent observations of the NN Serpentis post-common envelope binary system
have revealed eclipse timing variations that have been attributed to the
presence of two Jovian-mass exoplanets. Under the assumption that these planets
are real and survived from the binary's Main Sequence state, we reconstruct
initial binaries that give rise to the present NN Ser configuration and test
the dynamical stability of the original system. Under standard assumptions
about binary evolution, we find that survival of the planets through the entire
Main Sequence life-time is very unlikely. Hence, we conclude that the planets
are not survivors from before the Common Envelope phase, implying that either
they formed recently out of material ejected from the primary, or that the
observed signals are of non-planetary origin.
