diff --git a/abrechenbarkeit.lua b/abrechenbarkeit.lua
index d29cf20..190bea7 100755
--- a/abrechenbarkeit.lua
+++ b/abrechenbarkeit.lua
@@ -91,10 +91,12 @@ local stylesheet = io.open("style.css"):read("a")
 local script = io.open("script.js"):read("a")
 
 local function format(template, params)
-    return string.gsub(template, "{([%w\\.!]+)}", function(n)
-        local raw = n:sub(1,1) ~= "!"
-        if raw then n = n:sub(2) end
-        local s = format(params[n] or translations[n] or "NIL TEMPLATE", params)
+    params = params or {}
+    if template == nil then return "NIL TEMPLATE" end
+    return string.gsub(template, "{([%w_\\.!]+)}", function(n)
+        local raw = n:sub(1, 1) ~= "!"
+        if not raw then n = n:sub(2) end
+        local s = format(params[n] or translations[n] or "NIL PARAM", params)
         return raw and s or escape(s)
     end)
 end
diff --git a/locale/de.ini b/locale/de.ini
index c549161..babbbd9 100644
--- a/locale/de.ini
+++ b/locale/de.ini
@@ -1,3 +1,4 @@
+[abrechenbarkeit]
 appname=Abrechenbarkeit
 about=Über
 field.amount=Menge
diff --git a/locale/en.ini b/locale/en.ini
index 1deac2a..5eecfaf 100644
--- a/locale/en.ini
+++ b/locale/en.ini
@@ -1,3 +1,4 @@
+[abrechenbarkeit]
 appname=Abrechenbarkeit
 about=About
 field.amount=Amount