diff -Nur orig/DEBIAN/postinst changes/DEBIAN/postinst
--- orig/DEBIAN/postinst	2016-09-06 17:23:37.000000000 +0200
+++ changes/DEBIAN/postinst	2016-11-01 15:06:34.497650285 +0100
@@ -34,10 +34,17 @@
 	else
 		if grep -q '^DISTRIB_ID="*Univention"*$' /etc/lsb-release
 		then
-			/usr/share/egroupware/doc/rpm-build/post_install.php \
-            	--distro univention \
-				--admin_user "Administrator" \
-				--admin_passwd "*unchanged*" 2>&1 | /usr/bin/tee -a $install_log
+
+			if [ -n "$DOCKER_HOST_NAME" -a -n "$DB_HOST" ]; then
+				# docker UCS setup, use appcenter join script
+				:
+			else
+				# normal UCS setup
+				/usr/share/egroupware/doc/rpm-build/post_install.php \
+					--distro univention \
+					--admin_user "Administrator" \
+					--admin_passwd "*unchanged*" 2>&1 | /usr/bin/tee -a $install_log
+			fi
 		else
 			# Get configuration passwords
 			db_get "egroupware/header/user"