diff --git a/sdk_container/src/third_party/portage-stable/eclass/acct-group.eclass b/sdk_container/src/third_party/portage-stable/eclass/acct-group.eclass
index a0ad860663..2c2c88cfc7 100644
--- a/sdk_container/src/third_party/portage-stable/eclass/acct-group.eclass
+++ b/sdk_container/src/third_party/portage-stable/eclass/acct-group.eclass
@@ -1,4 +1,4 @@
-# Copyright 2019-2023 Gentoo Authors
+# Copyright 2019-2024 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 # @ECLASS: acct-group.eclass
@@ -50,12 +50,12 @@ inherit user-info
 # << Eclass variables >>
 
 # @ECLASS_VARIABLE: ACCT_GROUP_NAME
-# @INTERNAL
 # @DESCRIPTION:
 # The name of the group.  This is forced to ${PN} and the policy
-# prohibits it from being changed.
+# prohibits it from being changed.  The variable is left writable for
+# use in overlays; package naming restrictions would prohibit some
+# otherwise-valid group names.
 ACCT_GROUP_NAME=${PN}
-readonly ACCT_GROUP_NAME
 
 # @ECLASS_VARIABLE: ACCT_GROUP_ID
 # @REQUIRED
@@ -96,8 +96,9 @@ acct-group_pkg_pretend() {
 	[[ ${ACCT_GROUP_ID} -ge -1 ]] || die "Ebuild error: ACCT_GROUP_ID=${ACCT_GROUP_ID} invalid!"
 	local group_id=${ACCT_GROUP_ID}
 
-	# check for the override
-	local override_name=${ACCT_GROUP_NAME^^}
+	# check for the override, use PN in case this is an overlay and
+	# ACCT_GROUP_NAME is not PN and not valid in a bash variable name
+	local override_name=${PN^^}
 	local override_var=ACCT_GROUP_${override_name//-/_}_ID
 	if [[ -n ${!override_var} ]]; then
 		group_id=${!override_var}
@@ -132,8 +133,9 @@ acct-group_pkg_pretend() {
 acct-group_src_install() {
 	debug-print-function ${FUNCNAME} "${@}"
 
-	# check for the override
-	local override_name=${ACCT_GROUP_NAME^^}
+	# check for the override, use PN in case this is an overlay and
+	# ACCT_GROUP_NAME is not PN and not valid in a bash variable name
+	local override_name=${PN^^}
 	local override_var=ACCT_GROUP_${override_name//-/_}_ID
 	if [[ -n ${!override_var} ]]; then
 		ewarn "${override_var}=${!override_var} override in effect, support will not be provided."