correcting missing elements to the oai client to support the newer libxml packages.

Author: Terry Reese

lib/oai/client/header.rb

@@ -7,7 +7,7 @@ def initialize(element)
       @status = get_attribute(element, 'status')
       @identifier = xpath(element, './/identifier')
       @datestamp = xpath(element, './/datestamp')
-      @set_spec = xpath(element, './/setSpec')
+      @set_spec = xpath_all(element, './/setSpec')
     end
 
     def deleted?

lib/oai/client/response.rb

@@ -17,7 +17,12 @@ def initialize(doc)
           code = error.attributes['code']
         when 'LibXML::XML::Node'
           message = error.content
-          code = error.attributes('code')
+          code = ""
+          if defined?(error.property) == nil
+              code = error.attributes['code']
+           else
+              code.property('code')
+           end
       end
       raise OAI::Exception.new(message, code)
     end