diff --git a/roles/xmpp_server/tasks/main.yml b/roles/xmpp_server/tasks/main.yml
index b56eb5e490441b82eab7a92ccb6db312f5a545fe..d2fe10ce5687cc9e36050ec94b4ef698d4723874 100644
--- a/roles/xmpp_server/tasks/main.yml
+++ b/roles/xmpp_server/tasks/main.yml
@@ -25,29 +25,29 @@
 
 - name: Deploy XMPP TLS private key
   copy: dest="/etc/ssl/private/{{ ansible_fqdn }}_xmpp.key" content="{{ xmpp_tls_key }}"
-        mode=640 owner=root group=prosody
+        mode=0640 owner=root group=prosody
   notify:
     - Restart Prosody
 
 - name: Deploy XMPP TLS certificate
   copy: dest="/etc/ssl/certs/{{ ansible_fqdn }}_xmpp.pem" content="{{ xmpp_tls_certificate }}"
-        mode=644 owner=root group=root
+        mode=0644 owner=root group=root
   notify:
     - Restart Prosody
 
 - name: Deploy configuration file for checking certificate validity via cron
   copy: content="/etc/ssl/certs/{{ ansible_fqdn }}_xmpp.pem" dest="/etc/check_certificate/{{ ansible_fqdn }}_xmpp.conf"
-        owner=root group=root mode=644
+        owner=root group=root mode=0644
 
 - name: Set-up directory for storing additional Prosody modules
-  file: path=/usr/local/lib/prosody/modules/ state=directory mode=755 owner=root group=root
+  file: path=/usr/local/lib/prosody/modules/ state=directory mode=0755 owner=root group=root
 
 - name: Deploy the Prosody mod_auth_ldap module
   get_url: url=https://hg.prosody.im/prosody-modules/raw-file/tip/mod_auth_ldap/mod_auth_ldap.lua
            dest=/usr/local/lib/prosody/modules/mod_auth_ldap.lua
 
 - name: Set-up file permissions for the Prosody mod_auth_ldap module
-  file: dest=/usr/local/lib/prosody/modules/mod_auth_ldap.lua owner=root group=root mode=644
+  file: dest=/usr/local/lib/prosody/modules/mod_auth_ldap.lua owner=root group=root mode=0644
 
 - name: Deploy Prosody configuration file
   template: src=prosody.cfg.lua.j2 dest=/etc/prosody/prosody.cfg.lua
@@ -63,7 +63,7 @@
   service: name=prosody state=started
 
 - name: Deploy firewall configuration for XMPP server
-  copy: src="ferm_xmpp.conf" dest="/etc/ferm/conf.d/30-xmpp.conf" owner=root group=root mode=640
+  copy: src="ferm_xmpp.conf" dest="/etc/ferm/conf.d/30-xmpp.conf" owner=root group=root mode=0640
   notify:
     - Restart ferm