Unfortunately, fetchmail will *never* succeed in trying to unload this
particular message, so it hangs around for ever.
Isn't fetchmail supposed to be able to run unattended without me having to
constantly monitor it and manually fetch the mails it can't cope with?
Is the problem that fetchmail is internally broken and can't be fixed?
This strikes me as incorrect behaviour: fetchmail should either 1. drop
this message on the ground (is there a setting to enable this behaviour?);
or 2. forward it as an attachment to the configured postmaster (I can cope
with that).