In order to sort your email based on POPFile's classification, use your email client's filtering ability to sort the email into a folder.
For example, POPFile may classify an email like so:
Then, you could create a rule or macro in your email client to move any email with that line in the header to a spam folder, play a sound, or whatever else you like. Note in many mail clients, you won't see the X-Text-Classification in your default email display. This text will be added to your email headers, which are usually hidden by default. See your email client's documentation for how to display complete header information.
note: If you are already using some rules or macros in your email client, Please take care about the priority of them. Some email clients check the rules in order, and do only the actions assigned to the rules matched at first.