Bzr index hangs on 100% CPU

I tried to index a shared no-trees repository to facilitate Loggerhead's search, but it's been hanging at the following step for hours:

$ bzr index /var/lib/bzr/trunk
[##############| ] Indexing...:Saving group 3/4

CPU has been at 100% per top:

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
6268 bzr 25 0 2038m 2.0g 3048 R 100 51.8 256:36.50 bzr

Here's the branch info:

$ bzr info -v /var/lib/bzr/trunk
Repository branch (format: unnamed)
Location:
  shared repository: .
  repository branch: trunk

Format:
       control: Meta directory format 1
        branch: Branch format 6
    repository: Repository format 2a - rich roots, group compression and chk inventories

Branch history:
      1727 revisions
       761 days old
   first revision: Fri 2007-10-05 06:02:22 +0000
  latest revision: Wed 2009-11-04 14:33:42 -0800

Repository:
      1909 revisions

$ bzr --version
Bazaar (bzr) 2.0.0
  Python interpreter: /usr/bin/python 2.4.3
  Python standard library: /usr/lib/python2.4
  Platform: Linux-2.6.18-128.1.10.el5PAE-i686-with-redhat-5.2-Final
  bzrlib: /usr/lib/python2.4/site-packages/bzrlib
  Bazaar configuration: /home/bzr/.bazaar
  Bazaar log file: /home/bzr/.bzr.log

I installed bzr-search by:

$ bzr checkout lp:bzr-search
$ cd bzr-search
$ sudo python setup.py install

Let me know if there is any more info I can provide. I'm going to kill the process for now.