diff --git a/src/apps/http/altcp_proxyconnect.c b/src/apps/http/altcp_proxyconnect.c
index 3d5e7e83..d487620e 100644
--- a/src/apps/http/altcp_proxyconnect.c
+++ b/src/apps/http/altcp_proxyconnect.c
@@ -576,6 +576,10 @@ const struct altcp_functions altcp_proxyconnect_functions = {
   altcp_default_get_tcp_addrinfo,
   altcp_default_get_ip,
   altcp_default_get_port
+#if LWIP_TCP_KEEPALIVE
+  , altcp_default_keepalive_disable
+  , altcp_default_keepalive_enable
+#endif
 #ifdef LWIP_DEBUG
   , altcp_default_dbg_get_tcp_state
 #endif