Index: modules/proxy/proxy_util.c
===================================================================
--- modules/proxy/proxy_util.c	(revision 1035508)
+++ modules/proxy/proxy_util.c	(working copy)
@@ -2018,6 +2018,7 @@
 #if APR_HAS_THREADS
     (*conn)->inreslist = 0;
 #endif
+    (*conn)->cleaned = 0;
 
     return OK;
 }
@@ -2026,10 +2027,13 @@
                                                proxy_conn_rec *conn,
                                                server_rec *s)
 {
-    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
-                 "proxy: %s: has released connection for (%s)",
-                 proxy_function, conn->worker->hostname);
-    connection_cleanup(conn);
+    if (!conn->cleaned) {
+        ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
+                "proxy: %s: has released connection for (%s)",
+                proxy_function, conn->worker->hostname);
+        connection_cleanup(conn);
+        conn->cleaned = 1;
+    }
 
     return OK;
 }
Index: modules/proxy/mod_proxy_http.c
===================================================================
--- modules/proxy/mod_proxy_http.c	(revision 1035508)
+++ modules/proxy/mod_proxy_http.c	(working copy)
@@ -1817,9 +1817,36 @@
                     ap_proxy_buckets_lifetime_transform(r, bb, pass_bb);
 
                     /* found the last brigade? */
-                    if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(bb))) {
+                    if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(pass_bb))) {
+
                         /* signal that we must leave */
                         finish = TRUE;
+
+                        /* the brigade may contain transient buckets that contain
+                         * data that lives only as long as the backend connection.
+                         * Force a setaside so these transient buckets become heap
+                         * buckets that live as long as the request.
+                         */
+                        for (e = APR_BRIGADE_FIRST(pass_bb); e
+                                != APR_BRIGADE_SENTINEL(pass_bb); e
+                                = APR_BUCKET_NEXT(e)) {
+                            apr_bucket_setaside(e, r->pool);
+                        }
+
+                        /* finally it is safe to clean up the brigade from the
+                         * connection pool, as we have forced a setaside on all
+                         * buckets.
+                         */
+                        apr_brigade_cleanup(bb);
+
+                        /* make sure we release the backend connection as soon
+                         * as we know we are done, so that the backend isn't
+                         * left waiting for a slow client to eventually
+                         * acknowledge the data.
+                         */
+                        ap_proxy_release_connection(backend->worker->scheme,
+                                backend, r->server);
+
                     }
 
                     /* try send what we read */
@@ -1831,8 +1858,8 @@
                     }
 
                     /* make sure we always clean up after ourselves */
+                    apr_brigade_cleanup(pass_bb);
                     apr_brigade_cleanup(bb);
-                    apr_brigade_cleanup(pass_bb);
 
                 } while (!finish);
             }
@@ -1843,6 +1870,14 @@
             ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                          "proxy: header only");
 
+            /* make sure we release the backend connection as soon
+             * as we know we are done, so that the backend isn't
+             * left waiting for a slow client to eventually
+             * acknowledge the data.
+             */
+            ap_proxy_release_connection(backend->worker->scheme,
+                    backend, r->server);
+
             /* Pass EOS bucket down the filter chain. */
             e = apr_bucket_eos_create(c->bucket_alloc);
             APR_BRIGADE_INSERT_TAIL(bb, e);
Index: modules/proxy/mod_proxy.h
===================================================================
--- modules/proxy/mod_proxy.h	(revision 1035508)
+++ modules/proxy/mod_proxy.h	(working copy)
@@ -248,6 +248,7 @@
     int          need_flush;/* Flag to decide whether we need to flush the
                              * filter chain or not */
     void         *forward;  /* opaque forward proxy data */
+    int          cleaned:1; /* connection cleaned? */
 } proxy_conn_rec;
 
 typedef struct {