dhcp agent on Network node failed to start

I have a multi-node devstack setup. It used to be working fine. After updating it to the latest, network node didn't work anymore. The dhcp agent failed to start with the error:

             OSError: [Errno 13] Permission denied: '/var/lib/quantum'

It seemed that state_path was not configured in the config file, and /var/lib/quantum didn't exist on my network node.

Checking the commit history, found this change:

stacker@NetworkNode:~/devstack$ git show 3c6e9a5ac20d60e915d6d54cce3a0ac65da85108
commit 3c6e9a5ac20d60e915d6d54cce3a0ac65da85108
Author: Akihiro MOTOKI <email address hidden>
Date: Tue Feb 26 14:50:56 2013 +0900

    Set state_path to quantum.conf

    This change is required to make quantum security groups support of
    OVS/LinuxBridge plugins work.

    Previously state_path was configured in each agent config files in
    Quantum, but it is moved to quantum.conf. This change follows it.

    Change-Id: I290dc98878661375cf8a31a53d857433de0e5462

diff --git a/lib/quantum b/lib/quantum
index 0fef1ae..3466162 100644
--- a/lib/quantum
+++ b/lib/quantum
@@ -442,7 +442,6 @@ function _configure_quantum_dhcp_agent() {
     iniset $Q_DHCP_CONF_FILE DEFAULT verbose True
     iniset $Q_DHCP_CONF_FILE DEFAULT debug True
     iniset $Q_DHCP_CONF_FILE DEFAULT use_namespaces $Q_USE_NAMESPACE
- iniset $Q_DHCP_CONF_FILE DEFAULT state_path $DATA_DIR/quantum
     iniset $Q_DHCP_CONF_FILE DEFAULT root_helper "$Q_RR_COMMAND"

Revert the change, things started working. I believe that the above change would work for single-node setup, but not for multi node without additional manual configuration.

My question is that is this a bug?

thanks