Lire accepts qmail-send Qmail™ log files where each line starts with the timestamp in numerical (with fraction) format: 982584201.511524. qmail-smtpd logfiles are not (yet) supported.
If you use multilog, you will have to filter your log file through tai64nfraq.
If you redirect your Qmail™ logs to syslog, you can run lr_desyslog (included in Lire) to remove the extra syslog timestamp:
$ lr_desyslog qmail < qmail-syslog.log > qmail.log
Example 9.5. Qmail™ Log Sample
998545829.342079 new msg 6416 998545829.342350 info msg 6416: bytes 2657 from \ <bounce-debian-hurd=john.doe-debian-hurd=john.doe.1@1.mail.example.com> \ qp 22423 uid 71 998545829.356889 starting delivery 1808: msg 6416 to local \ john.doe.2@2.mail.example.com 998545829.357096 status: local 1/10 remote 0/20 998545829.445754 delivery 1808: success: did_0+0+1/ 998545829.445976 status: local 0/10 remote 0/20 998545829.446056 end msg 6416 998545832.186954 new msg 6416 998545832.187213 info msg 6416: bytes 1957 from \ <dns-return-13543-john-dns=john.doe.3@3.mail.example.com> qp 22431 uid 71 998545832.196806 starting delivery 1809: msg 6416 to local \ john.doe.4@2.mail.example.com