diff --git a/pytrustnfe/xml/__init__.py b/pytrustnfe/xml/__init__.py
index 1f721e2..066d567 100644
--- a/pytrustnfe/xml/__init__.py
+++ b/pytrustnfe/xml/__init__.py
@@ -16,11 +16,20 @@ def recursively_empty(e):
     return all((recursively_empty(c) for c in e.iterchildren()))
 
 
-def render_xml(path, template_name, remove_empty, **nfe):
-    for item in nfe:
-        if type(nfe[item]) is str:
-            nfe[item] = nfe[item].strip()
+def recursively_normalize(vals):
+    for item in vals:
+        if type(vals[item]) is str:
+            vals[item] = vals[item].strip()
+        elif type(vals[item]) is dict:
+            recursively_normalize(vals[item])
+        elif type(vals[item]) is list:
+            for a in vals[item]:
+                recursively_normalize(a)
+    return vals
+
 
+def render_xml(path, template_name, remove_empty, **nfe):
+    nfe = recursively_normalize(**nfe)
     env = Environment(
         loader=FileSystemLoader(path), extensions=['jinja2.ext.with_'])