What I was actually trying to get at is this: should the server set the \Seen flags for messages for which it has returned data or not?
Yes, it should.
Better question is should it set \Seen flag for messages for which it didn't return the BINARY data (but might have returned other things). I would guess not, but RFC doesn't mention this. IMHO the whole implicit \Seen setting is just evil and it'd been better for BINARY not to support it at all.
Argh! Very good point.
