Hello, I am using following python code to load an XML Schema to be used for later XML valiadtion: #------------ import urllib from lxml import etree schema_url = "http://schemas.opengis.net/wcs/1.1/wcsGetCapabilities.xsd" schema_base = "http://schemas.opengis.net/wcs/1.1/" schema = etree.XMLSchema( etree.XML( urllib.urlopen( schema_url ).read() , base_url = schema_base ) ) #------------ The etree.XMLSchema fails with following error: File "xmlschema.pxi", line 103, in lxml.etree.XMLSchema.__init__ (src/lxml/lxml.etree.c:116069) lxml.etree.XMLSchemaParseError: Element '{http://www.w3.org/2001/XMLSchema}import': Skipping import of schema located at 'http://www.w3.org/2001/xml.xsd' for the namespace 'http://www.w3.org/XML/1998/namespace', since this namespace was already imported with the schema located at 'http://schemas.opengis.net/gml/3.1.1/smil/xml-mod.xsd'., line 20 The issue is obvious two included independent schema documents include the same schema, but I see no reason why the XMLSchema constructor should fail by throwing an exception, N.B., when the exception says it is skipping the action. It should continue to work rather than to give it up. So far I managed to test this issue on several Linux distributions with the same result: Ubuntu 10.4 lxml 2.2.4 Debian Lenny lxml 2.1.1 ScinetificLin.6 lxml 2.2.3 I plan to download and check the latest 2.3 version and possibly to try an alternative XML Schema validator. But maybe I could get a faster answer from someone of you saving me some time. Also, I am not sure whether this issue should be reported as a bug, but I guess so. Thank you. Martin