uschar *remove_headers; /* Remove these headers */
uschar *return_path; /* Overriding (rewriting) return path */
uschar *debug_string; /* Debugging output */
+ uschar *max_parallel; /* Number of concurrent instances */
uschar *message_size_limit; /* Biggest message this transport handles */
uschar *headers_rewrite; /* Rules for rewriting headers */
rewrite_rule *rewrite_rules; /* Parsed rewriting rules */