A copy of what was sent to CTM support: Currently PowerMail behaves in this fashion: If an email filter "X" have the action "Don't show recent messages" and a connection is made and new messages are downloaded but are filtered according to said filter "X" and no other new messages are downloaded, the Recent Messages window still comes to foreground showing an empty window (or non new messages from earlier downloads). This provided obviously that the preferences is set to open the Recent Messages Window when new mail messages arrives.
A more logical behavior and a more naturally user expected one would be under the circumstances above: -> The Recent Messages Window do not come to foreground unless there are new messages that are going to be visible in it. Mikael Tech facts: PM 5.5.3 Swedish/ SpamSieve 2.6.4 Swedish | OS X 10.4.8 | Powerbook G4/400 Mhz | 1GB RAM | 80GB HD