diff --git a/salt/states/jboss7.py b/salt/states/jboss7.py
index 67db6cb5f2..0272e96e4c 100644
--- a/salt/states/jboss7.py
+++ b/salt/states/jboss7.py
@@ -531,6 +531,12 @@ def __check_dict_contains(dct, dict_name, keys, comment='', result=True):
 
 
 def __append_comment(new_comment, current_comment=''):
+    if current_comment is None and new_comment is None:
+        return ''
+    if current_comment is None:
+        return new_comment
+    if new_comment is None:
+        return current_comment
     return current_comment+'\n'+new_comment