diff --git a/ChangeLog b/ChangeLog
index cbefb0009..96c42b60a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -48,6 +48,7 @@ http://weechat.org/files/releasenotes/ReleaseNotes-devel.html[release notes]
 * lua: fix interpreter used after unload of a script
 * perl: fix context used after unload of a script
 * python: fix interpreter used after unload of a script
+* relay: fix freeze after /upgrade when many disconnected clients still exist
 * relay: fix NULL pointer when reading buffer lines for irc backlog
 * scripts: fix crash when a signal is received with type "int" and NULL pointer
   in signal_data
diff --git a/src/plugins/relay/weechat/relay-weechat.c b/src/plugins/relay/weechat/relay-weechat.c
index ba3cfbe1c..697e6867f 100644
--- a/src/plugins/relay/weechat/relay-weechat.c
+++ b/src/plugins/relay/weechat/relay-weechat.c
@@ -260,7 +260,14 @@ relay_weechat_alloc_with_infolist (struct t_relay_client *client,
                                        &relay_weechat_free_buffers_nicklist);
         RELAY_WEECHAT_DATA(client, hook_timer_nicklist) = NULL;
 
-        relay_weechat_hook_signals (client);
+        if (RELAY_CLIENT_HAS_ENDED(client))
+        {
+            RELAY_WEECHAT_DATA(client, hook_signal_buffer) = NULL;
+            RELAY_WEECHAT_DATA(client, hook_hsignal_nicklist) = NULL;
+            RELAY_WEECHAT_DATA(client, hook_signal_upgrade) = NULL;
+        }
+        else
+            relay_weechat_hook_signals (client);
     }
 }