Eudora allows filtering based on any mail header, which is great - everything can be done completely in the background, without changing the subject line of the message!

So the easiest method of setting up filters for POPFile's classification is to turn on the X-Text-Classification insertion on POPFile's Bucket page.

1. From the menu select Tools → Filters.
2. On the left of this window is the list of all your filters; to the right is the area where you create filters.
3. Click New to create a new filter.
4. In the first Header: field on the right, type X-Text-Classification:bucket_name, and in the box next to it type the name of your bucket, e.g. spam
5. Now go down to the Actions area. From the first drop-down list, select the action Transfer To.
6. Click the box that appears to the right of this, select New… and into the dialog that appears type spam
7. Click OK to confirm this.
8. In the second Actions drop-down list, select Skip Rest.
   • When filters are invoked, each message is matched against each filter in the filters list in order from top to bottom. If a message meets a filter’s criteria, the actions are done as specified in the filter until there are no more actions. Then the message is matched against the next filter. The Skip Rest action makes Eudora skip the rest of the filters in the filters list for that message and start filtering the next message, again going from top to bottom down the filters list.
9. Note: in the POPFile web interface, under the Bucket tab, check that the Subject Line Modification option is turned off.