BoxCollection#find should only find V1 box when searching for vbox

lib/vagrant/box_collection.rb

@@ -198,6 +198,9 @@ module Vagrant
         return Box.new(name, provider, box_directory.dirname)
       end
 
+      # If we're looking for a VirtualBox box, then we check if there is
+      # a V1 box.
+      if provider == :virtualbox
         # Check if a V1 version of this box exists, and if so, raise an
         # exception notifying the caller that the box exists but needs
         # to be upgraded. We don't do the upgrade here because it can be
@@ -211,6 +214,7 @@ module Vagrant
           @logger.warn("V1 box found: #{name}")
           raise Errors::BoxUpgradeRequired, :name => name
         end
+      end
 
       # Didn't find it, return nil
       @logger.info("Box not found: #{name} (#{provider})")

test/unit/vagrant/box_collection_test.rb

@@ -168,6 +168,14 @@ describe Vagrant::BoxCollection do
       expect { instance.find("foo", :virtualbox) }.
         to raise_error(Vagrant::Errors::BoxUpgradeRequired)
     end
+
+    it "should return nil if there is a V1 box but we're looking for another provider" do
+      # Create a V1 box
+      environment.box1("foo")
+
+      # Test
+      instance.find("foo", :another_provider).should be_nil
+    end
   end
 
   describe "upgrading" do