diff --git a/include/lighttpd/connection.h b/include/lighttpd/connection.h
index 496e2ef..4312c4e 100644
--- a/include/lighttpd/connection.h
+++ b/include/lighttpd/connection.h
@@ -93,17 +93,15 @@ struct liConnection {
 	} stats;
 };
 
+/* Internal functions */
 LI_API liConnection* li_connection_new(liWorker *wrk);
-LI_API void li_connection_reset(liConnection *con);
-LI_API void li_connection_reset_keep_alive(liConnection *con);
 LI_API void li_connection_free(liConnection *con);
+LI_API void li_connection_reset(liConnection *con);
 
-LI_API void li_connection_error(liConnection *con);
-LI_API void li_connection_internal_error(liConnection *con);
-
-LI_API void li_connection_handle_direct(liConnection *con);
-LI_API void li_connection_handle_indirect(liConnection *con, liPlugin *p);
+/** aborts an active connection, calls all plugin cleanup handlers */
+LI_API void li_connection_error(liConnection *con); /* used in worker.c */
 
+/* public function */
 LI_API gchar *li_connection_state_str(liConnectionState state);
 
 #endif
diff --git a/include/lighttpd/response.h b/include/lighttpd/response.h
index fa1890c..3e2a3f1 100644
--- a/include/lighttpd/response.h
+++ b/include/lighttpd/response.h
@@ -15,7 +15,7 @@ LI_API void li_response_init(liResponse *resp);
 LI_API void li_response_reset(liResponse *resp);
 LI_API void li_response_clear(liResponse *resp);
 
-LI_API void li_response_send_headers(liConnection *con);
+LI_API gboolean li_response_send_headers(liConnection *con);
 LI_API void li_response_send_error_page(liConnection *con);
 
 #endif
diff --git a/src/main/connection.c b/src/main/connection.c
index 52933ba..95ec627 100644
--- a/src/main/connection.c
+++ b/src/main/connection.c
@@ -5,6 +5,9 @@
 /* only call it from the worker context the con belongs to */
 void worker_con_put(liConnection *con); /* worker.c */
 
+static void li_connection_reset_keep_alive(liConnection *con);
+static void li_connection_internal_error(liConnection *con);
+
 static void parse_request_body(liConnection *con) {
 	if ((con->state > LI_CON_STATE_HANDLE_MAINVR || con->mainvr->state >= LI_VRS_READ_CONTENT) && !con->in->is_closed) {
 		li_ev_io_add_events(con->wrk->loop, &con->sock_watcher, EV_READ);
@@ -30,11 +33,15 @@ static void forward_response_body(liConnection *con) {
 	liVRequest *vr = con->mainvr;
 	if (con->state >= LI_CON_STATE_HANDLE_MAINVR) {
 		if (!con->response_headers_sent) {
-			con->response_headers_sent = TRUE;
 			if (CORE_OPTION(LI_CORE_OPTION_DEBUG_REQUEST_HANDLING).boolean) {
 				VR_DEBUG(vr, "%s", "write response headers");
 			}
-			li_response_send_headers(con);
+			con->response_headers_sent = TRUE;
+			if (!li_response_send_headers(con)) {
+				con->response_headers_sent = FALSE;
+				li_connection_internal_error(con);
+				return;
+			}
 		}
 
 		if (vr->response.transfer_encoding & LI_HTTP_TRANSFER_ENCODING_CHUNKED) {
@@ -101,14 +108,18 @@ void li_connection_error(liConnection *con) {
 	worker_con_put(con);
 }
 
-void li_connection_internal_error(liConnection *con) {
+static void li_connection_internal_error(liConnection *con) {
 	liVRequest *vr = con->mainvr;
 	if (con->response_headers_sent) {
-		VR_ERROR(vr, "%s", "Couldn't send '500 Internal Error': headers already sent");
+		if (CORE_OPTION(LI_CORE_OPTION_DEBUG_REQUEST_HANDLING).boolean) {
+			VR_DEBUG(vr, "%s", "Couldn't send '500 Internal Error': headers already sent");
+		}
 		li_connection_error(con);
 	} else {
 		liHttpVersion v;
-		VR_ERROR(vr, "%s", "internal error");
+		if (CORE_OPTION(LI_CORE_OPTION_DEBUG_REQUEST_HANDLING).boolean) {
+			VR_DEBUG(vr, "%s", "internal error");
+		}
 
 		/* We only need the http version from the http request */
 		v = con->mainvr->request.http_version;
@@ -557,8 +568,7 @@ void li_connection_reset(liConnection *con) {
 	con->throttled = FALSE;
 }
 
-void server_check_keepalive(liServer *srv);
-void li_connection_reset_keep_alive(liConnection *con) {
+static void li_connection_reset_keep_alive(liConnection *con) {
 	liVRequest *vr = con->mainvr;
 	ev_timer_stop(con->wrk->loop, &con->keep_alive_data.watcher);
 	{
diff --git a/src/main/response.c b/src/main/response.c
index 97c6ef8..2dfecc7 100644
--- a/src/main/response.c
+++ b/src/main/response.c
@@ -20,15 +20,13 @@ void li_response_clear(liResponse *resp) {
 	resp->transfer_encoding = LI_HTTP_TRANSFER_ENCODING_IDENTITY;
 }
 
-void li_response_send_headers(liConnection *con) {
+gboolean li_response_send_headers(liConnection *con) {
 	GString *head;
 	liVRequest *vr = con->mainvr;
 
 	if (vr->response.http_status < 100 || vr->response.http_status > 999) {
 		VR_ERROR(vr, "wrong status: %i", vr->response.http_status);
-		con->response_headers_sent = FALSE;
-		li_connection_internal_error(con);
-		return;
+		return FALSE;
 	}
 
 	head = g_string_sized_new(8*1024-1);
@@ -128,6 +126,8 @@ void li_response_send_headers(liConnection *con) {
 
 	g_string_append_len(head, CONST_STR_LEN("\r\n"));
 	li_chunkqueue_append_string(con->raw_out, head);
+
+	return TRUE;
 }
 
 #define SET_LEN_AND_RETURN_STR(x) \