libvirt package apparently not installed for nova unittest builder

Seems like a bunch of unit tests are being skipped in the gate-nova-unittests Jenkins job:

    test_unfilter_instance_undefines_nwfilter SKIP: Test requires libvirt
LibvirtConnTestCase
    test_attach_invalid_volume_type OK 0.01
    test_available_least_handles_missing OK 0.01
    test_broken_connection SKIP: Test requires libvirt
    test_destroy_saved SKIP: Test requires libvirt
    test_ensure_filtering_rules_for_instance_timeout SKIP: Test requires libvirt
    test_get_all_block_devices OK 0.01
    test_get_connector OK 0.01
    test_get_console_output_file SKIP: Test requires libvirt
    test_get_console_output_pty SKIP: Test requires libvirt
    test_get_guest_config OK 0.15
    test_get_guest_config_with_root_device_name OK 0.09
    test_get_guest_config_with_two_nics OK 0.45
    test_get_host_ip_addr OK 0.01
    test_get_instance_disk_info_works_correctly SKIP: Test requires libvirt
    test_immediate_delete SKIP: Test requires libvirt
    test_list_instances OK 0.01
    test_live_migration_raises_exception SKIP: Test requires libvirt
    test_lxc_container_and_uri OK 0.09
    test_multi_nic OK 0.15
    test_pre_block_migration_works_correctly SKIP: Test requires libvirt
    test_pre_live_migration_works_correctly OK 0.01
    test_snapshot_in_ami_format SKIP: Test requires libvirt
    test_snapshot_in_qcow2_format SKIP: Test requires libvirt
    test_snapshot_in_raw_format SKIP: Test requires libvirt
    test_snapshot_no_image_architecture SKIP: Test requires libvirt
    test_snapshot_no_original_image SKIP: Test requires libvirt
    test_spawn_with_network_info SKIP: Test requires libvirt
    test_volume_in_mapping OK 0.01
    test_xml_and_uri OK 0.66
    test_xml_and_uri_no_kernel OK 0.63
    test_xml_and_uri_no_ramdisk OK 0.61
    test_xml_and_uri_no_ramdisk_no_kernel OK 0.94
    test_xml_and_uri_rescue OK 0.40
    test_xml_disk_bus_ide OK 0.15
    test_xml_disk_bus_virtio OK 0.16
    test_xml_disk_driver OK 0.29
    test_xml_disk_prefix OK 0.53
    test_xml_uuid OK 0.16
LibvirtConnectionTestCase
    test_finish_migration OK 0.03
    test_finish_revert_migration OK 0.03
    test_migrate_disk_and_power_off OK 0.03
    test_migrate_disk_and_power_off_exception OK 0.02
    test_wait_for_running OK 0.01
LibvirtNonblockingTestCase
    test_connection_to_primitive SKIP: Test requires libvirt

https://jenkins.openstack.org/job/gate-nova-unittests/2012/console

Is the python libvirt package being installed into this test environment?