milter-checkrcpt
sendmail milter plugin for recipient checking
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    Package versionmilter-checkrcpt-0.3p4
 - 
    MaintainerOkan Demirmen
 
The milter-checkrcpt plugin can be used with the milter API of
sendmail(8) to filter mails with invalid recipients.  The validity of a
recipient address is determined by querying another mail server over
SMTP.