diff --git a/Dockerfile b/Dockerfile
index 7741320..262fdf3 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -64,7 +64,9 @@ RUN apt-get update -qq >/dev/null 2>&1 \
 
 # x-layer 2: prepare php source compilation and add jenkins user to sudo group
 RUN set -xe \
-    echo "jenkins ALL=(ALL:ALL) NOPASSWD: ALL" > /etc/sudoers \
+    && mkdir ~/.gnupg \
+    && echo "disable-ipv6" >> ~/.gnupg/dirmngr.conf \
+    && echo "jenkins ALL=(ALL:ALL) NOPASSWD: ALL" > /etc/sudoers \
 	&& cd /usr/src \
 	&& curl -fSL "https://secure.php.net/get/$PHP_FILENAME/from/this/mirror" -o php.tar.xz \
 	&& echo "$PHP_SHA256 *php.tar.xz" | sha256sum -c - \