diff --git a/sdk_container/src/third_party/portage-stable/eclass/libtool.eclass b/sdk_container/src/third_party/portage-stable/eclass/libtool.eclass
index a38f415882..e70fd715ae 100644
--- a/sdk_container/src/third_party/portage-stable/eclass/libtool.eclass
+++ b/sdk_container/src/third_party/portage-stable/eclass/libtool.eclass
@@ -1,10 +1,12 @@
 # Copyright 1999-2021 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
+# Flatcar: Support EAPI 0 and 4.
+
 # @ECLASS: libtool.eclass
 # @MAINTAINER:
 # base-system@gentoo.org
-# @SUPPORTED_EAPIS: 5 6 7 8
+# @SUPPORTED_EAPIS: 0 4 5 6 7 8
 # @BLURB: quickly update bundled libtool code
 # @DESCRIPTION:
 # This eclass patches ltmain.sh distributed with libtoolized packages with the
@@ -18,7 +20,7 @@ if [[ -z ${_LIBTOOL_ECLASS} ]]; then
 _LIBTOOL_ECLASS=1
 
 case ${EAPI:-0} in
-	5|6) DEPEND=">=app-portage/elt-patches-20170815" ;;
+	0|4|5|6) DEPEND=">=app-portage/elt-patches-20170815" ;;
 	7|8) BDEPEND=">=app-portage/elt-patches-20170815" ;;
 	*) die "${ECLASS}: EAPI ${EAPI} not supported" ;;
 esac