1. A network security system for processing e-mail transactions, the system comprising: an e-mail sever; an e-mail client; a transparent relay configured to receive and process e-mail communications between the e-mail client and the e-mail server, the transparent relay being configured to examine e-mail communications for network security policy violations, to perform policy actions on particular e-mail communications that violate a network security policy, and to relay particular e-mail communications that do not violate a network security policy; and a router configured to divert to the transparent relay e-mail communications between the e-mail client and the e-mail server.