[chef] client getting 404 on chef server URI /en-US/nodes

hi. this is wierd. today i brought a few ec2 clients out of a stopped
state and attempted to put them thru their chef-client run, as usual.
suddenly they are trying to access a URI on the chef server that doesn't
exist: /en-US/*  .. thus they're failing with 404.

all my other nodes use this same chef server, same chef-client version
(chef-full-0.10.10-1, CentOS 5.8), and are not exhibiting this behavior
currently.

here's a bit of log from one of the failing clients. you can see the last time
chef ran back in August, it was accessing the correct URI. upon its first run
today, it tried the right URI, then suddenly, inexplicably tried prepending
that URI with "/en-US".

10/26 
23:
 
 chef]# grep "via GET to chef.prod.gogiants.com" /var/log/chef/client.log | 
tail -6
[Wed, 08 Aug 2012 20:25:18 +0000] DEBUG: Sending HTTP Request via GET to 
chef.prod.gogiants.com:443/data/secrets/creds-prod
[Wed, 08 Aug 2012 20:25:18 +0000] DEBUG: Sending HTTP Request via GET to 
chef.prod.gogiants.com:443/data/yum/yum-tasks
[Fri, 26 Oct 2012 23:31:46 +0000] DEBUG: Sending HTTP Request via GET to 
chef.prod.gogiants.com:443/nodes/test-mobile.prod.gogiants.com
[Fri, 26 Oct 2012 23:31:46 +0000] DEBUG: Sending HTTP Request via GET to 
chef.prod.gogiants.com:443/en-US/nodes/test-mobile.prod.gogiants.com
[Fri, 26 Oct 2012 23:31:48 +0000] DEBUG: Sending HTTP Request via GET to 
chef.prod.gogiants.com:443/en-US/nodes
[Fri, 26 Oct 2012 23:35:12 +0000] DEBUG: Sending HTTP Request via GET to 
chef.prod.gogiants.com:443/en-US/clients

does anyone know what's going on here? what to look for?

more complete log output is in a gist:
https://gist.github.com/3962319

thanks!
kallen