1. A method for filtering messages, the method comprising: receiving a message over a network communication interface; executing instructions stored in memory, the instructions being executed by a processor to: process the received message using one or more reliable classifiers that are associated with a higher level of accuracy than at least one trained classifier from a plurality of available classifiers, wherein the one or more reliable classifiers are associated with a feature count, classify the received message using the one or more reliable classifiers and the feature count, track a feature of the classified message based on the classification, wherein the tracked feature and one or more other tracked features are stored in a table and the feature count accounts for a number of times the tracked feature appeared in the classified message, and process the received message based on the classification, wherein processing of the received message includes blocking the received message when the received message is classified as spam or allowing the received message to be forwarded to a recipient when the message is classified as a good message; receiving a new indication that the message is spam or good, the new indication regarding a different feature count associated with a different feature; updating the trained classifier by updating the feature count in accordance with the different feature count in the new indication; identifying that a subsequently received message is spam based on the updated feature count and a whitelist count, wherein the whitelist count is associated with a number of times that at least one of the feature or the different feature appears in one or more whitelisted messages; and blocking the subsequently received message based on the subsequently received message being classified as spam in accordance with the updated feature count.