End-to-end encryption schemes that support operations over ciphertext are of utmost importance for commercial private party Wireless Sensor Network implementations to become meaningful and profitable. For Wireless Sensor Networks, we demonstrated in our previous work that Privacy Homomorphisms, when used for this purpose, offer two striking advantages apart from end-to-end concealment of data and ability to operate on ciphertexts: flexibility by keyless aggregation and conservation and balancing of aggregator backbone energy. We offered proof of concept by applying a certain Privacy Homomorphism for sensor network applications that rely on the addition operation. But a large class of aggregator functions like median computation or finding maximum/minimum rely exclusively on comparison operations. Unfortunately, as shown by Rivest, et. al., any Privacy Homomorphism is insecure even against ciphertext only attacks, if they support comparison operations. In this paper we show that a p...