Japanese cellular competitors share spimmer blacklists

DoCoMo, Au, and J-Phone are sharing blacklists of spimmers who send unsolicited commercial IMs to their customers' phones. While the convenience is undoubtably fantastic, I worry about this: with three companies sharing black-lists, the lists' maintainers suddenly have the power to shut anyone up across the Japanese mobile universe. What if someone decides to blacklist the kinds of messages that took down a goverment in the Phillipines? More to the point: who decides what's spim and how do you appeal the decision?