Comment 18 for bug 1578576

Just tried and still getting the same problem:
samba:
  Installed: 2:4.3.9+dfsg-0ubuntu0.14.04.2~ppa1
  Candidate: 2:4.3.9+dfsg-0ubuntu0.14.04.2~ppa1
  Version table:
 *** 2:4.3.9+dfsg-0ubuntu0.14.04.2~ppa1 0
        500 http://ppa.launchpad.net/mdeslaur/testing/ubuntu/ trusty/main amd64 Packages
        100 /var/lib/dpkg/status
     2:4.3.9+dfsg-0ubuntu0.14.04.1 0
        500 http://optubunturepository.MYDOMAIN.net/ubuntu/ trusty-updates/main amd64 Packages
        500 http://optubunturepository.MYDOMAIN.net/ubuntu/ trusty-security/main amd64 Packages
     2:4.1.6+dfsg-1ubuntu2 0
        500 http://optubunturepository.MYDOMAIN.net/ubuntu/ trusty/main amd64 Packages

syslog:
May 10 14:31:11 optsquidproxy kernel: [ 206.928248] ntlm_auth[2264]: segfault at 8 ip 00007f68e2aba9b0 sp 00007fff384ec2c8 error 4 in libsamba-security.so.0[7f68e2aaf000+1b000]

cache.log:
2016/05/10 14:32:42| WARNING: ntlmauthenticator #1 exited
2016/05/10 14:32:42| Too few ntlmauthenticator processes are running (need 1/10)
2016/05/10 14:32:42| Starting new helpers
2016/05/10 14:32:42| helperOpenServers: Starting 1/10 'ntlm_auth' processes
2016/05/10 14:32:42| ERROR: NTLM Authentication Helper '0x7f8368efb268' crashed!.
2016/05/10 14:32:42| ERROR: NTLM Authentication validating user. Error returned 'BH Internal error'