diff --git a/roles/xmpp_server/molecule/default/files/lua_ldap_backports_pin b/roles/xmpp_server/molecule/default/files/lua_ldap_backports_pin
new file mode 100644
index 0000000000000000000000000000000000000000..b4a6225d422dec0f39930322222c13eb0e7545e9
--- /dev/null
+++ b/roles/xmpp_server/molecule/default/files/lua_ldap_backports_pin
@@ -0,0 +1,9 @@
+#
+# This file contains pinning information for deploying the backported
+# version of lud-ldap that supports Lua 5.2 (for use with the Prosody
+# XMPP server).
+#
+
+Package: lua-ldap
+Pin: release a=buster-backports
+Pin-Priority: 600
diff --git a/roles/xmpp_server/molecule/default/prepare.yml b/roles/xmpp_server/molecule/default/prepare.yml
index 55225ac5666f9e9552b645b0510b88ac88137d12..f9487affda50e6c40543cf2df1befaf085015f9b 100644
--- a/roles/xmpp_server/molecule/default/prepare.yml
+++ b/roles/xmpp_server/molecule/default/prepare.yml
@@ -138,6 +138,14 @@
         mode: 0644
         state: present
 
+    - name: Deploy lua-ldap package pin for testing Stretch -> Buster upgrade scenario (no need to pin the package in Buster)
+      copy:
+        src: "lua_ldap_backports_pin"
+        dest: "/etc/apt/preferences.d/lua-ldap"
+        owner: root
+        group: root
+        mode: 0644
+
 - hosts: clients
   become: true
   tasks:
diff --git a/roles/xmpp_server/molecule/default/tests/test_default_buster.py b/roles/xmpp_server/molecule/default/tests/test_default_buster.py
new file mode 100644
index 0000000000000000000000000000000000000000..d9ddbd345bbfaf400f1de2c2748d52ddf4fd27ab
--- /dev/null
+++ b/roles/xmpp_server/molecule/default/tests/test_default_buster.py
@@ -0,0 +1,20 @@
+import os
+
+import testinfra.utils.ansible_runner
+
+
+testinfra_hosts = testinfra.utils.ansible_runner.AnsibleRunner(
+    os.environ['MOLECULE_INVENTORY_FILE']).get_hosts('parameters-*-buster64')
+
+
+def test_lua_ldap_pin_and_version(host):
+    """
+    Tests if lua-ldap package is not pinned to the backports
+    repository.
+    """
+
+    pin_configuration_file = host.file("/etc/apt/preferences.d/lua-ldap")
+    lua_ldap = host.package("lua-ldap")
+
+    assert not pin_configuration_file.exists
+    assert "bpo" not in lua_ldap.version
diff --git a/roles/xmpp_server/tasks/main.yml b/roles/xmpp_server/tasks/main.yml
index bd0c26a420fc952e47e9f04f2fa51a38e6697d51..25ac54d51cdca07a93782450fb5dc742875b221c 100644
--- a/roles/xmpp_server/tasks/main.yml
+++ b/roles/xmpp_server/tasks/main.yml
@@ -21,6 +21,12 @@
     mode: 0644
   when: "ansible_distribution_release == 'stretch'"
 
+- name: Drop the Pin lua-ldap package (if machine was upgraded from Debian Stretch)
+  file:
+    path: "/etc/apt/preferences.d/lua-ldap"
+    state: absent
+  when: "ansible_distribution_release != 'stretch'"
+
 - name: Add Prosody repository apt key
   apt_key:
     data: "{{ lookup('file', 'prosody-debian-packages.gpg') }}"