diff --git a/support/scripts/mkusers b/support/scripts/mkusers
index 08f3344518..87a36a89a1 100755
--- a/support/scripts/mkusers
+++ b/support/scripts/mkusers
@@ -450,7 +450,7 @@ main() {
                 auto_id=${AUTO_USER_ID}
             fi
             for g in ${groups//,/ }; do
-                add_one_group "${g}" ${auto_id}
+                add_one_group "${g}" "${auto_id}"
             done
         fi
     done