diff --git a/py/Boinc/boincxml.py b/py/Boinc/boincxml.py
index 6761356cc3..2631e870b2 100644
--- a/py/Boinc/boincxml.py
+++ b/py/Boinc/boincxml.py
@@ -50,6 +50,7 @@ def set_element(node, new_data):
     if node.firstChild and node.firstChild.data:
         node.firstChild.data = str(new_data)
     else:
+        # different versions of pyxml have different interface (!)
         try:
             new_data_node = xml.dom.minidom.Text()
         except: