Rails 3 automatically adding X-UA-Compatible header?

Does Rails 3 automatically add a header if you are using IE8? I am seeing the meta tag for X-UA-Compatible set to "IE=8.0000" a开发者_如何学运维nd it's messing up one of my views.

I can't seem to find anything else that would be doing it, so figured I'd ask the brains here.

Thanks, Ruprict

If we have a look at all middlewares loaded in a vanilla rails3 app:

rake middleware
(in /private/tmp/bla)
use ActionDispatch::Static
use Rack::Lock
use ActiveSupport::Cache::Strategy::LocalCache
use Rack::Runtime
use Rails::Rack::Logger
use ActionDispatch::ShowExceptions
use ActionDispatch::RemoteIp
use Rack::Sendfile
use ActionDispatch::Callbacks
use ActiveRecord::ConnectionAdapters::ConnectionManagement
use ActiveRecord::QueryCache
use ActionDispatch::Cookies
use ActionDispatch::Session::CookieStore
use ActionDispatch::Flash
use ActionDispatch::ParamsParser
use Rack::MethodOverride
use ActionDispatch::Head
use ActionDispatch::BestStandardsSupport
run Bla::Application.routes

there's ActionDispatch::BestStandardsSupport which source is setting the X-UA-Compatible header, not with IE=8.000 though. Do you run 3.0.0?