Open Stack

I'm trying to modify a 3rd party test setup to use zuul, but I'm seeing the following error when I start up the zuul server:

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2014-04-15 09:09:18,910 ERROR gerrit.GerritWatcher: Exception on ssh event stream:
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/zuul/lib/gerrit.py", line 64, in _run
    key_filename=self.keyfile)
  File "/usr/local/lib/python2.7/dist-packages/paramiko/client.py", line 342, in connect
    self._auth(username, password, pkey, key_filenames, allow_agent, look_for_keys)
  File "/usr/local/lib/python2.7/dist-packages/paramiko/client.py", line 533, in _auth
    raise saved_exception
PasswordRequiredException: Private key file is encrypted
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Here is my zuul config file (/etc/zuul/zuul.conf):

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[gearman]
server=127.0.0.1

[gearman_server]
start=true
log_config=/etc/zuul/gearman-logging.conf

[gerrit]
server=review.openstack.org
user=zuul
sshkey=/var/lib/zuul/.ssh/id_rsa
#user=jenkins
#sshkey=/var/lib/jenkins/.ssh/id_rsa
#user=cisco_neutron_ci
#sshkey=/home/cisco_neutron_ci/.ssh/id_rsa

[zuul]
layout_config=/etc/zuul/layout.yaml
log_config=/etc/zuul/logging.conf
state_dir=/var/lib/zuul
git_dir=/var/lib/zuul/git
push_change_refs=false
url_pattern=http://128.107.233.28:8080/job/(job.name)/(build.number)
status_url=http://status.openstack.org/zuul/
job_name_in_report=true
zuul_url=https://review.openstack.org
===========================================

I've tried using various users for the zuul-to-gerrit connection (zuul, jenkins, and our corporate gerrit account username).

Is there something basic that I'm missing in the config?

Appreciate any help,
Dane