cannot convert lv to type thin-pool on trusty

[Ryan Harper]

1. $ lsb_release -rd
Description: Ubuntu 14.04.2 LTS
Release: 14.04

2. $ apt-cache policy lvm2
lvm2:
  Installed: 2.02.98-6ubuntu2
  Candidate: 2.02.98-6ubuntu2
  Version table:
 *** 2.02.98-6ubuntu2 0
        500 http://archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages
        100 /var/lib/dpkg/status

3. lvconvert to type thin-pool warns about destrying data on the target LV's and thin type, this is the output on vivid:
ubuntu@lvm02:~$ sudo lvconvert --type thin-pool --poolmetadata vg/pool0meta vg/pool0
  WARNING: Converting logical volume vg/pool0 and vg/pool0meta to pool's data and metadata volumes.
  THIS WILL DESTROY CONTENT OF LOGICAL VOLUME (filesystem etc.)
Do you really want to convert vg/pool0 and vg/pool0meta? [y/n]: y
  Logical volume "lvol0" created
  Converted vg/pool0 to thin pool.
ubuntu@lvm02:~$ sudo lvs -a
  LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
  [lvol0_pmspare] vg ewi------- 1.00g
  pool0 vg twi-a-tz-- 10.00g 0.00 0.01
  [pool0_tdata] vg Twi-ao---- 10.00g
  [pool0_tmeta] vg ewi-ao---- 1.00g

4. lvconvert returns 0, but does not convert the lv to type thin-pool

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: lvm2 2.02.98-6ubuntu2
ProcVersionSignature: User Name 3.13.0-52.85-generic 3.13.11-ckt18
Uname: Linux 3.13.0-52-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.10
Architecture: amd64
Date: Thu May 21 15:35:20 2015
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: lvm2
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.