- move async activation into the server
- implement async queues

diff --git a/server/queue.c b/server/queue.c
index 87e85a0..a639ebe 100644
--- a/server/queue.c
+++ b/server/queue.c
@@ -112,6 +112,7 @@
     no_get_fd,                 /* get_fd */
     no_flush,                  /* flush */
     no_get_file_info,          /* get_file_info */
+    NULL,                      /* queue_async */
     msg_queue_destroy          /* destroy */
 };