Install fails when using a preseed file that adds a PPA using: d-i apt-setup/local0/...

This bug was fixed in the package ubiquity - 2.11.32

---------------
ubiquity (2.11.32) quantal; urgency=low

  [ Jeremy Bicha ]
  * Allow specifying a manual mount point in advanced partitioner
    (LP: #1047275).

  [ Dmitrijs Ledkovs ]
  * Revert test string, to a user friendly one as it is visible in the UI.
  * Automatic update of included source packages: base-installer
    1.122ubuntu11, partman-auto-lvm 45ubuntu3, tzsetup 1:0.26ubuntu12.
  * pep8 fixes in Riddell's code

  [ Colin Watson ]
  * Remove a couple of vestiges of migration-assistant.
  * Catch OverflowError as well as ValueError from datetime functions, for
    forward-compatibility with Python 3.3.
  * Use importlib rather than __import__.
  * Install fetch-url for apt-setup's local generator (LP: #1049535).

  [ Jonathan Riddell ]
  * ubiquity/plugins/ubi-partman.py and
    ubiquity/frontend/kde_components/PartAuto.py
   - add options for LUKS and LVM automatic partitioning to KDE frontend
     (LP: #1048712)

  [ Simon Steinbeiß ]
  * Disable xfwm4's compositor in ubiquity-dm to prevent screen-corruption
    (LP: #924909)
 -- Dmitrijs Ledkovs <email address hidden> Wed, 12 Sep 2012 22:45:51 +0100

I was able to test an install with the ISO this fix went into, it is still failing although in a slightly different place.

The error message is:
    ubuntu ubiquity" /bin/fetch-url: 4 .: Can't open /lib/preseed/preseed.sh

/lib/preseed doesn't appear to exist at all.

I wasn't certain if I needed to create a new bug report for this, if you need that I'm happy to do so.

This bug was fixed in the package debian-installer-utils - 1.91ubuntu4

---------------
debian-installer-utils (1.91ubuntu4) quantal; urgency=low

  * Remove unnecessary sourcing of preseed.sh from fetch-url (LP: #1049535).
 -- Colin Watson <email address hidden> Fri, 14 Sep 2012 12:28:43 +0100

This bug was fixed in the package ubiquity - 2.11.33

---------------
ubiquity (2.11.33) quantal; urgency=low

  [ Dmitrijs Ledkovs ]
  * Make Add/Remove/Change toolbar not have a background. Thanks to
    askubuntu and andrewsomething.
  * Fix TypeError in a debug statement when resize is not possible due to
    small total disk space.
  * Remove more of Python 2 support. We are not going back to the __future__.
  * Use py3compile, instead of pycompile.

  [ Stéphane Graber ]
  * Fix drop_all_privileges to also set LOGNAME which is required by firefox
    to contact an existing instance. (LP: #446679)

  [ Colin Watson ]
  * Automatic update of included source packages: debian-installer-utils
    1.91ubuntu4 (LP: #1049535), flash-kernel 3.0~rc.4ubuntu23.
 -- Colin Watson <email address hidden> Fri, 14 Sep 2012 12:40:52 +0100

I believe I'm seeing this bug (or one very similar) in precise as well. I wasn't able to find the exact bzr commit fixing this; can someone comment on whether the change might be SRUable? Should I fill out the SRU template in the description of this bug? Thanks!