VM halt works.

lib/vagrant/action/vm/halt.rb

@@ -13,7 +13,7 @@ module Vagrant
 
             if env[:vm].state != :poweredoff
               env[:ui].info I18n.t("vagrant.actions.vm.halt.force")
-              env[:vm].vm.stop
+              env[:vm].driver.halt
             end
 
             # Sleep for a second to verify that the VM properly

lib/vagrant/driver/virtualbox.rb

@@ -87,6 +87,11 @@ module Vagrant
         execute("modifyvm", @uuid, *args)
       end
 
+      # Halts the virtual machine.
+      def halt
+        execute("controlvm", @uuid, "poweroff")
+      end
+
       # Imports the VM with the given path to the OVF file. It returns
       # the UUID as a string.
       def import(ovf, name)