Como evitar probe de contas???

Pessoal,

como evitar isso no sendmail? Esses probes de contas de e-mail são um inferno. Existem alguma configuração ou pacote que monitora essas tentativas e bloqueia o IP da origem???

isso é só um pedaço do log. Imaginem que a palhaçada começou com
[email protected]

[]´s
Marcelo

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