Spurious warning during upgrade of sharded cluster

When upgrading from 2.6 to 2.8, the mongod will spam the config server logs with the following message:
The "bad serverID set in setShardVersion and none in info: EOO"

I believe this was introduced in the fix for SERVER-16733 and should be harmless, but need to verify. Message goes away once config servers are upgrade to 3.0.0