Due to the emergence of multimedia context-rich applications and services over wireless networks, networking protocols and services are becoming more and more integrated, thus relying on context and application information to operate. Further, wireless protocols and services have employed information from several network layers and the environment, breaking the layering paradigm. In order to cope with this increasing reliance on knowledge, we propose MANKOP, a middleware for MANETs that instantiates a new networking plane. The Knowledge Plane (KP) is a distributed entity that stores and disseminates information concerning the network, its services and the environment, orchestrating the collaboration among cross-layer protocols, autonomic management solutions and context-aware services. We use MANKOP to support the autonomic reconfiguration of a P2P network over MANETs. Simulation results show that the MANKOP-enabled solution is applicable to more scenarios than the classic approaches, as the network adapts its query dissemination strategy to match the current conditions of the peers.