Originally Posted by EULA Section 4, subsection B paragraph 3
B. You agree that you shall not, under any circumstances,
(iii) host, provide or develop matchmaking services for the Game or intercept, emulate or redirect the communication protocols used by Blizzard Entertainment in any way, including, without limitation, through protocol emulation, tunneling, packet sniffing, modifying or adding components to the Game, use of a utility program or any other techniques now known or hereafter developed, for any purpose, including, but not limited to, unauthorized network play over the Internet, network play utilizing commercial or non-commercial gaming networks or as part of content aggregation networks; or