1. A method for improving a statistical message classifier, comprising: testing a message with a machine classifier, wherein the machine classifier is capable of making a classification of the message and the machine classifier is a reliable classifier having a probability of erroneous classification of less than one percent; and updating the statistical message classifier according to the classification made by the machine classifier, wherein the statistical message classifier is configured to detect an unsolicited message and comprises a knowledge base that tracks the spam probability of features in classified messages.