Summary form only given. There are many issues that should be considered when porting systems or applications to mobile ad-hoc network (MANET) environments. In particular, security and performance of MANET have gained wide attention; yet, PKI (public key infrastructure) is no exception. There were some serious attempts to address the issues of providing certificate authority (CA) services in MANETs. In this paper, we present an enhanced design over the existing approaches in order to provide CA services in MANET. We show a new approach that utilizes cooperative caching between the clients to increase system availability even when the network is partitioned. Moreover, it reduces the need to increase the number of participant mobile certificate authority (MOCA) nodes used to increase the availability of the system; thus reducing the overhead of replicas synchronization and key refreshing occurred when the number of MOCAs is relatively large. By careful design and under reasonable assumptions, we show that certificate caching could be integrated and deployed in MANET without sacrificing the system security.