  In principle the Zeno effect controlled-sign gate of Franson et al's (PRA 70,
062302, 2004) is a deterministic two-qubit optical gate. However, when
realistic values of photon loss are considered its fidelity is significantly
reduced. Here we consider the use of measurement based quantum processing
techniques to enhance the operation of the Zeno gate. With the help of quantum
teleportation, we show that it is possible to achieve a Zeno CNOT gate (GC-Zeno
gate) that gives (near) unit fidelity and moderate probability of success of
0.76 with a one-photon to two-photon transmission ratio $\kappa=10^4$. We
include some mode-mismatch effects and estimate the bounds on the mode overlap
and $\kappa$ for which fault tolerant operation would be possible.
