diff --git a/remote-curl.c b/remote-curl.c
index a331bae..28b2a31 100644
--- a/remote-curl.c
+++ b/remote-curl.c
@@ -290,6 +290,7 @@
 	int out;
 	struct strbuf result;
 	unsigned gzip_request : 1;
+	unsigned initial_buffer : 1;
 };
 
 static size_t rpc_out(void *ptr, size_t eltsize,
@@ -300,6 +301,7 @@
 	size_t avail = rpc->len - rpc->pos;
 
 	if (!avail) {
+		rpc->initial_buffer = 0;
 		avail = packet_read_line(rpc->out, rpc->buf, rpc->alloc);
 		if (!avail)
 			return 0;
@@ -314,6 +316,29 @@
 	return avail;
 }
 
+#ifndef NO_CURL_IOCTL
+curlioerr rpc_ioctl(CURL *handle, int cmd, void *clientp)
+{
+	struct rpc_state *rpc = clientp;
+
+	switch (cmd) {
+	case CURLIOCMD_NOP:
+		return CURLIOE_OK;
+
+	case CURLIOCMD_RESTARTREAD:
+		if (rpc->initial_buffer) {
+			rpc->pos = 0;
+			return CURLIOE_OK;
+		}
+		fprintf(stderr, "Unable to rewind rpc post data - try increasing http.postBuffer\n");
+		return CURLIOE_FAILRESTART;
+
+	default:
+		return CURLIOE_UNKNOWNCMD;
+	}
+}
+#endif
+
 static size_t rpc_in(const void *ptr, size_t eltsize,
 		size_t nmemb, void *buffer_)
 {
@@ -370,8 +395,13 @@
 		 */
 		headers = curl_slist_append(headers, "Expect: 100-continue");
 		headers = curl_slist_append(headers, "Transfer-Encoding: chunked");
+		rpc->initial_buffer = 1;
 		curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, rpc_out);
 		curl_easy_setopt(slot->curl, CURLOPT_INFILE, rpc);
+#ifndef NO_CURL_IOCTL
+		curl_easy_setopt(slot->curl, CURLOPT_IOCTLFUNCTION, rpc_ioctl);
+		curl_easy_setopt(slot->curl, CURLOPT_IOCTLDATA, rpc);
+#endif
 		if (options.verbosity > 1) {
 			fprintf(stderr, "POST %s (chunked)\n", rpc->service_name);
 			fflush(stderr);