def create_folder(opts)
      opts = opts.clone
      req = build_soap! do |type, builder|
        if(type == :header)
        else
          builder.nbuild.CreateFolder {|x|
            x.parent.default_namespace = @default_ns
            builder.parent_folder_id!(opts[:parent_folder_id])
            builder.folders!(opts[:folders])
          }
        end
      end
      do_soap_request(req)
    end
def create_folder(opts)
      opts = opts.clone
      req = build_soap! do |type, builder|
        if(type == :header)
        else
          builder.nbuild.CreateFolder {|x|
            x.parent.default_namespace = @default_ns
            builder.parent_folder_id!(opts[:parent_folder_id])
            builder.folders!(opts[:folders])
          }
        end
      end
      do_soap_request(req)
    end
------------- Folder Operations ------------
 Creates folders, calendar folders, contacts folders, tasks folders, and search folders.
 @see http://msdn.microsoft.com/en-us/library/aa563574.aspx CreateFolder

 @param [Hash] opts
 @option opts [Hash] :parent_folder_id A hash with either the name of a
   folder or it's numerical ID.
   See: http://msdn.microsoft.com/en-us/library/aa565998.aspx
   {:id => :root}  or {:id => 'myfolderid#'}
 @option opts [Array<Hash>] :folders An array of hashes of folder types
   that conform to input for build_xml!
   @example [
     {:folder =>
       {:display_name => "New Folder"}},
     {:calendar_folder =>
       {:folder_id => {:id => 'blah', :change_key => 'blah'}}}