diff -up ./src/chameleon/core/utils.py.orig ./src/chameleon/core/utils.py
--- ./src/chameleon/core/utils.py.orig	2011-02-02 17:07:32.530262435 -0500
+++ ./src/chameleon/core/utils.py	2011-02-02 17:08:13.160988253 -0500
@@ -16,6 +16,12 @@ except ImportError:
     def adapts(*interfaces):
         pass
 
+try:
+    from xml.etree.ElementTree import ParseError
+except ImportError:
+    class ParseError(object):
+        pass
+
 import sys
 import interfaces
 import htmlentitydefs
@@ -137,7 +143,7 @@ def validate(string):
     
     try:
         import_elementtree().fromstring(validation_string)
-    except xml.parsers.expat.ExpatError:
+    except (xml.parsers.expat.ExpatError, ParseError):
         raise ValidationError(string)
 
 def elements_with_attribute(element, ns, name, value=None):