Index: modules/proxy/mod_proxy_wstunnel.c
===================================================================
--- modules/proxy/mod_proxy_wstunnel.c	(revision 1801041)
+++ modules/proxy/mod_proxy_wstunnel.c	(working copy)
@@ -39,7 +39,9 @@ typedef struct ws_baton_t {
 
 static void proxy_wstunnel_callback(void *b);
 
-static int proxy_wstunnel_pump(ws_baton_t *baton, apr_time_t timeout, int try_poll) {
+static int proxy_wstunnel_pump(ws_baton_t *baton, apr_time_t timeout,
+                               int try_poll, int *replied)
+{
     request_rec *r = baton->r;
     conn_rec *c = r->connection;
     proxy_conn_rec *conn = baton->proxy_connrec;
@@ -53,7 +55,7 @@ static void proxy_wstunnel_callback(void *b);
     apr_status_t rv;
     apr_bucket_brigade *bb_i = baton->bb_i;
     apr_bucket_brigade *bb_o = baton->bb_o;
-    int done = 0, replied = 0;
+    int done = 0;
 
     do { 
         rv = apr_pollset_poll(pollset, timeout, &pollcnt, &signalled);
@@ -91,7 +93,7 @@ static void proxy_wstunnel_callback(void *b);
                     done |= ap_proxy_transfer_between_connections(r, backconn,
                                                                   c, bb_i, bb_o,
                                                                   "backend",
-                                                                  &replied,
+                                                                  replied,
                                                                   AP_IOBUFSIZE,
                                                                   0)
                                                                  != APR_SUCCESS;
@@ -143,13 +145,7 @@ static void proxy_wstunnel_callback(void *b);
 
     ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r,
             "finished with poll() - cleaning up");
-
-    if (!replied) {
-        return HTTP_BAD_GATEWAY;
-    }
-    else {
-        return OK;
-    }
+    return OK;
 }
 
 static void proxy_wstunnel_finish(ws_baton_t *baton) { 
@@ -181,12 +177,14 @@ static void proxy_wstunnel_cancel_callback(void *b
  *  We don't need the invoke_mtx, since we never put multiple callback events
  *  in the queue.
  */
-static void proxy_wstunnel_callback(void *b) { 
+static void proxy_wstunnel_callback(void *b)
+{ 
     int status;
     ws_baton_t *baton = (ws_baton_t*)b;
     proxyws_dir_conf *dconf = ap_get_module_config(baton->r->per_dir_config, &proxy_wstunnel_module);
     apr_pool_clear(baton->subpool);
-    status = proxy_wstunnel_pump(baton, dconf->async_delay, dconf->mpm_can_poll);
+    status = proxy_wstunnel_pump(baton, dconf->async_delay,
+                                 dconf->mpm_can_poll, NULL);
     if (status == SUSPENDED) {
         apr_pollfd_t *pfd;
 
@@ -315,6 +313,8 @@ static int proxy_wstunnel_request(apr_pool_t *p, r
     int status;
     proxyws_dir_conf *dconf = ap_get_module_config(r->per_dir_config, &proxy_wstunnel_module);
     const char *upgrade_method = *worker->s->upgrade ? worker->s->upgrade : "WebSocket";
+    ap_filter_t *saved_output_filters, *saved_proto_output_filters;
+    int replied = 0;
 
     header_brigade = apr_brigade_create(p, backconn->bucket_alloc);
 
@@ -367,6 +367,8 @@ static int proxy_wstunnel_request(apr_pool_t *p, r
     pollfd.desc.s = client_socket;
     apr_pollset_add(pollset, &pollfd);
 
+    saved_output_filters = r->output_filters;
+    saved_proto_output_filters = r->proto_output_filters;
     ap_remove_input_filter_byhandle(c->input_filters, "reqtimeout");
 
     r->output_filters = c->output_filters;
@@ -389,10 +391,12 @@ static int proxy_wstunnel_request(apr_pool_t *p, r
     apr_pool_create(&baton->subpool, r->pool);
 
     if (!dconf->mpm_can_poll) {
-        status = proxy_wstunnel_pump(baton, dconf->idle_timeout, dconf->mpm_can_poll);
+        status = proxy_wstunnel_pump(baton, dconf->idle_timeout,
+                                     dconf->mpm_can_poll, &replied);
     }  
     else { 
-        status = proxy_wstunnel_pump(baton, dconf->async_delay, dconf->mpm_can_poll);
+        status = proxy_wstunnel_pump(baton, dconf->async_delay,
+                                     dconf->mpm_can_poll, &replied);
         apr_pool_clear(baton->subpool);
         if (status == SUSPENDED) {
             apr_pollfd_t *pfd;
@@ -420,19 +424,31 @@ static int proxy_wstunnel_request(apr_pool_t *p, r
                 return SUSPENDED;
             }
             else if (APR_STATUS_IS_ENOTIMPL(rv)) { 
-                ap_log_rerror(APLOG_MARK, APLOG_TRACE1, 0, r, APLOGNO(02544) "No async support");
-                status = proxy_wstunnel_pump(baton, dconf->idle_timeout, 0); /* force no async */
+                ap_log_rerror(APLOG_MARK, APLOG_TRACE1, 0, r,
+                              APLOGNO(02544) "No async support");
+                status = proxy_wstunnel_pump(baton, dconf->idle_timeout,
+                                             0, /* force no async */
+                                             &replied);
             }
             else { 
                 ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
                               APLOGNO(02543) "error creating websockets tunnel");
-                return HTTP_INTERNAL_SERVER_ERROR;
+                if (!replied) {
+                    status = HTTP_INTERNAL_SERVER_ERROR;
+                }
             }
         }
     }
 
-    if (status != OK) { 
-        /* Avoid sending error pages down an upgraded connection */
+    /* Avoid sending error pages down an upgraded connection */
+    if (!replied) {
+        r->output_filters = saved_output_filters;
+        r->proto_output_filters = saved_proto_output_filters;
+        if (status == OK) {
+            status = HTTP_BAD_GATEWAY;
+        }
+    }
+    else if (status != OK) { 
         if (status != HTTP_REQUEST_TIME_OUT) {
             r->status = status;
         }