return a 500 error code on ajax subscribe failure (see PR 445)

Author: michield

public_html/lists/index.php

@@ -278,9 +278,8 @@
 
                     echo 'FAIL';
 
-                    // thow an exception so the http status code is a 500
-                    // Internal Server Error, easily caught by jquery.ajax()
-                    throw new Exception( "Error: Subscribe attempt failed!" );
+                    // return a 500, so that it is more easily processed at the other end
+                    http_response_code( 500 );
 
                 }
                 break;