diff --git a/src/freedombone-app-xmpp b/src/freedombone-app-xmpp
index 3ee95270d081105408dbb079a012f619ce76bc23..eb6d23a856ef9773860e28fe561a53c0c8d6019c 100755
--- a/src/freedombone-app-xmpp
+++ b/src/freedombone-app-xmpp
@@ -697,6 +697,21 @@ function upgrade_xmppsend {
 
 }
 
+function prosody_set_parameter {
+    prosody_param_name="$1"
+    prosody_param_value="$2"
+
+    if ! grep -q "${prosody_param_name} " /etc/prosody/prosody.cfg.lua; then
+        echo "${prosody_param_name} = ${prosody_param_value};" >> /etc/prosody/prosody.cfg.lua
+        xmpp_restart=1
+    else
+        if ! grep -q "${prosody_param_name} = ${prosody_param_value};" /etc/prosody/prosody.cfg.lua; then
+            sed -i "s|${prosody_param_name} .*|${prosody_param_name} = ${prosody_param_value};|g" /etc/prosody/prosody.cfg.lua
+            xmpp_restart=1
+       fi
+    fi
+}
+
 function upgrade_xmpp {
     xmpp_restart=
 
@@ -725,25 +740,9 @@ function upgrade_xmpp {
         xmpp_restart=1
     fi
 
-    if grep -q 'http_upload_file_size_limit = 307200' /etc/prosody/prosody.cfg.lua; then
-        sed -i 's|http_upload_file_size_limit =.*|http_upload_file_size_limi t= 25165824|g' /etc/prosody/prosody.cfg.lua
-        xmpp_restart=1
-    fi
-
-    if grep -q 'muc_room_default_members_only = true' /etc/prosody/prosody.cfg.lua; then
-        sed -i 's|muc_room_default_members_only.*|muc_room_default_members_only = false;|g' /etc/prosody/prosody.cfg.lua
-        xmpp_restart=1
-    fi
-
-    if ! grep -q 'muc_tombstones' /etc/prosody/prosody.cfg.lua; then
-        sed -i '/muc_room_lock_timeout/a muc_tombstones = false;' /etc/prosody/prosody.cfg.lua
-        xmpp_restart=1
-    else
-        if ! grep -q 'muc_tombstones = false' /etc/prosody/prosody.cfg.lua; then
-            sed -i 's|muc_tombstones .*|muc_tombstones = false;|g' /etc/prosody/prosody.cfg.lua
-            xmpp_restart=1
-       fi
-    fi
+    prosody_set_parameter 'http_upload_file_size_limit' '25165824'
+    prosody_set_parameter 'muc_room_default_members_only' 'false'
+    prosody_set_parameter 'muc_tombstones' 'false'
 
     # extra battery saving
     prosody_add_module "csi_compat"