SecurePayAU: Send Content-Type headers

test/unit/gateways/secure_pay_au_test.rb
24 tests, 106 assertions, 0 failures, 0 errors, 0 pendings, 0 omissions, 0 notifications
100% passed

test/remote/gateways/remote_secure_pay_au_test.rb
18 tests, 56 assertions, 0 failures, 0 errors, 0 pendings, 2 omissions, 0 notifications
100% passed

lib/active_merchant/billing/gateways/secure_pay_au.rb

@@ -181,7 +181,7 @@ def build_request(action, body)
       end
 
       def commit(action, request)
-        response = parse(ssl_post(test? ? self.test_url : self.live_url, build_request(action, request)))
+        response = parse(ssl_post(test? ? self.test_url : self.live_url, build_request(action, request), {"Content-Type" => "text/xml; charset=utf-8"}))
 
         Response.new(
           success?(response),
@@ -241,7 +241,7 @@ def build_periodic_request(body)
 
       def commit_periodic(request)
         my_request = build_periodic_request(request)
-        response = parse(ssl_post(test? ? self.test_periodic_url : self.live_periodic_url, my_request))
+        response = parse(ssl_post(test? ? self.test_periodic_url : self.live_periodic_url, my_request, {"Content-Type" => "text/xml; charset=utf-8"}))
 
         Response.new(
           success?(response),