setcifsacl errors out, package missing idmap-plugin symlink

# lsb_release -rd
Description: Ubuntu 14.04 LTS
Release: 14.04

# apt-cache policy cifs-utils
cifs-utils:
  Installed: 2:6.0-1ubuntu2
  Candidate: 2:6.0-1ubuntu2

The cifs-utils package is missing a symlink to the idmap plugin; attempting to run setcifsacl errors out like so:

# setcifsacl -a "ACL:S-1-5-21-762712803-3572108623-4099884218-1003:ALLOWED/I/FULL" /data/test-file

ERROR: unable to initialize idmapping plugin: /etc/cifs-utils/idmap-plugin: cannot open shared object file: No such file or directory

The plugin is available, it's just a symlink needed to fix it even though idmap isn't being used (no winbind):

# mkdir /etc/cifs-utils
# ln -s /usr/lib/x86_64-linux-gnu/cifs-utils/idmapwb.so /etc/cifs-utils/idmap-plugin

# setcifsacl -a "ACL:S-1-5-21-762712803-3572108623-4099884218-1003:ALLOWED/I/FULL" /data/test-file

# getcifsacl /data/test-file
REVISION:0x1
CONTROL:0x8004
OWNER:S-1-5-21-762712803-3572108623-4099884218-1001
GROUP:S-1-5-21-762712803-3572108623-4099884218-513
ACL:S-1-5-21-762712803-3572108623-4099884218-500:ALLOWED/I/FULL
ACL:S-1-5-32-544:ALLOWED/I/FULL
ACL:S-1-5-21-762712803-3572108623-4099884218-1001:ALLOWED/I/FULL
ACL:S-1-5-18:ALLOWED/I/FULL
ACL:S-1-5-21-762712803-3572108623-4099884218-1003:ALLOWED/I/FULL

Reference: https://bugzilla.redhat.com/show_bug.cgi?id=985067