ubuntu error installing quantum-plugin-openvswitch-agent: apt-get install : Failed to fetch http://ppa.launchpad.net/openstack-ubuntu-testing/folsom-deps-staging/ubuntu/pool/main/p/python-cliff/python-cliff_1.1.2-0ubuntu2~cloud0_all.deb Size mismat

Trying to follow steps from http://docs.openstack.org/trunk/openstack-network/admin/content/install_quantum_agent_ovs.html and hit the below error. Any alternative way to install ?

apt-get -y install quantum-plugin-openvswitch-agent

root@ubantu:/home/krishna/quantum-2012.2/bin# apt-get -y --force-yes install quantum-plugin-openvswitch-agent
< -y --force-yes install quantum-plugin-openvswitch-agent
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
  dkms libjs-sphinxdoc libjs-underscore libyaml-0-2 openvswitch-common
  openvswitch-datapath-dkms openvswitch-switch python-amqplib python-anyjson
  python-cliff python-cmd2 python-decorator python-eventlet python-gflags
  python-greenlet python-iso8601 python-keystone python-keystoneclient
  python-kombu python-migrate python-netaddr python-passlib python-prettytable
  python-pyparsing python-pyudev python-quantum python-quantumclient
  python-routes python-sqlalchemy python-sqlalchemy-ext python-tempita
  python-yaml quantum-common quantum-plugin-openvswitch
Suggested packages:
  javascript-common python-amqplib-doc python-greenlet-dbg python-greenlet-dev
  python-greenlet-doc python-memcache python-boto python-couchdb
  python-kombu-doc python-pymongo ipython python-qt4 python-pyside.qtcore
  python-sqlalchemy-doc python-psycopg2 python-kinterbasdb python-pymssql
The following NEW packages will be installed:
  dkms libjs-sphinxdoc libjs-underscore libyaml-0-2 openvswitch-common
  openvswitch-datapath-dkms openvswitch-switch python-amqplib python-anyjson
  python-cliff python-cmd2 python-decorator python-eventlet python-gflags
  python-greenlet python-iso8601 python-keystone python-keystoneclient
  python-kombu python-migrate python-netaddr python-passlib python-prettytable
  python-pyparsing python-pyudev python-quantum python-quantumclient
  python-routes python-sqlalchemy python-sqlalchemy-ext python-tempita
  python-yaml quantum-common quantum-plugin-openvswitch
  quantum-plugin-openvswitch-agent
0 upgraded, 35 newly installed, 0 to remove and 12 not upgraded.
Need to get 503 kB/8,051 kB of archives.
After this operation, 38.8 MB of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
  libyaml-0-2 dkms libjs-underscore python-amqplib python-anyjson python-cmd2
  python-decorator python-greenlet python-eventlet python-gflags python-kombu
  python-tempita python-migrate python-netaddr python-pyparsing python-pyudev
  python-iso8601 python-routes python-passlib python-yaml
Get:1 http://ppa.launchpad.net/openstack-ubuntu-testing/folsom-deps-staging/ubuntu/ precise/main python-sqlalchemy all 0.7.8-1ubuntu1~cloud0 [475 kB]
Get:2 http://ppa.launchpad.net/openstack-ubuntu-testing/folsom-deps-staging/ubuntu/ precise/main python-cliff all 1.1.2-0ubuntu2~cloud0 [13.0 kB]
Get:3 http://ppa.launchpad.net/openstack-ubuntu-testing/folsom-deps-staging/ubuntu/ precise/main python-sqlalchemy-ext i386 0.7.8-1ubuntu1~cloud0 [14.2 kB]
Fetched 582 kB in 1s (379 kB/s)
Failed to fetch http://ppa.launchpad.net/openstack-ubuntu-testing/folsom-deps-staging/ubuntu/pool/main/s/sqlalchemy/python-sqlalchemy_0.7.8-1ubuntu1~cloud0_all.deb Size misma\
tch
Failed to fetch http://ppa.launchpad.net/openstack-ubuntu-testing/folsom-deps-staging/ubuntu/pool/main/p/python-cliff/python-cliff_1.1.2-0ubuntu2~cloud0_all.deb Size mismatch
Failed to fetch http://ppa.launchpad.net/openstack-ubuntu-testing/folsom-deps-staging/ubuntu/pool/main/s/sqlalchemy/python-sqlalchemy-ext_0.7.8-1ubuntu1~cloud0_i386.deb Size \
mismatch
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
root@ubantu:/home/krishna/quantum-2012.2/bin#
-m=-U:**--F1 ubuntu Bot (15675,46) (Shell:run)--11:33AM-------------