[Users] Exporting subjects

[Ralf Mardorf]

On Sun, 26 Mar 2017 10:43:34 -0700, sylpheed at 911networks.com wrote:
>> Subject: [Fail2Ban] Apache (scan): banned 91.200.12.86  

IIUC what you actually want is to filter all mails by the subject
matching e.g. "Fail2Ban" and instead of e.g. moving those mails to
different folders, you want to execute a script, sorting the subject by
IPs and to write e.g. a statistic to a log file. IOW A Claws filter is
used to get all subjects including "Fail2Ban" and executing e.g. a
shell script sorting and counting those subjects by their IPs.