diff --git a/lib/puppet/indirector/node/exec.rb b/lib/puppet/indirector/node/exec.rb
index d4faf74f4..9fa3c07ad 100644
--- a/lib/puppet/indirector/node/exec.rb
+++ b/lib/puppet/indirector/node/exec.rb
@@ -1,69 +1,77 @@
 require 'puppet/node'
 require 'puppet/indirector/exec'
 
 class Puppet::Node::Exec < Puppet::Indirector::Exec
   desc "Call an external program to get node information.  See
   the [External Nodes](http://docs.puppetlabs.com/guides/external_nodes.html) page for more information."
   include Puppet::Util
 
   def command
     command = Puppet[:external_nodes]
     raise ArgumentError, "You must set the 'external_nodes' parameter to use the external node terminus" unless command != "none"
     command.split
   end
 
   # Look for external node definitions.
   def find(request)
     output = super or return nil
 
     # Translate the output to ruby.
     result = translate(request.key, output)
 
+    # If defining a new environment then we check to see if
+    # the environment exists, if it does not then we raise
+    # an error instead of falling back to the 'production'
+    # environment.
+    if result[:environment] && !Puppet.lookup(:environments).get(result[:environment])
+      raise Puppet::Environments::EnvironmentNotFound, result[:environment]
+    end
+
     # Set the requested environment if it wasn't overridden
     # If we don't do this it gets set to the local default
     result[:environment] ||= request.environment.name
 
     create_node(request.key, result)
   end
 
   private
 
   # Proxy the execution, so it's easier to test.
   def execute(command, arguments)
     Puppet::Util::Execution.execute(command,arguments)
   end
 
   # Turn our outputted objects into a Puppet::Node instance.
   def create_node(name, result)
     node = Puppet::Node.new(name)
     set = false
     [:parameters, :classes, :environment].each do |param|
       if value = result[param]
         node.send(param.to_s + "=", value)
         set = true
       end
     end
 
     node.fact_merge
     node
   end
 
   # Translate the yaml string into Ruby objects.
   def translate(name, output)
     YAML.load(output).inject({}) do |hash, data|
       case data[0]
       when String
         hash[data[0].intern] = data[1]
       when Symbol
         hash[data[0]] = data[1]
       else
         raise Puppet::Error, "key is a #{data[0].class}, not a string or symbol"
       end
 
       hash
     end
 
   rescue => detail
       raise Puppet::Error, "Could not load external node results for #{name}: #{detail}", detail.backtrace
   end
 end