XSD Schema Parse Error with namespaced attributes

[admonkey]

When I generate the XSD using this sample xml (renamed to sample.xml.txt for github's uploader)

./schema-learn -t xsd simple.xml > simple.xsd

Then try to validate it with xmllint

xmllint --noout --schema simple.xsd simple.xml

I get schema parser errors failing to compile

simple.xsd:33: element attribute: Schemas parser error : Element '{http://www.w3.org/2001/XMLSchema}attribute', attribute 'name': 'dmd:lastModified' is not a valid value of the atomic type 'xs:NCName'.
simple.xsd:34: element attribute: Schemas parser error : Element '{http://www.w3.org/2001/XMLSchema}attribute', attribute 'name': 'dmd:startDate' is not a valid value of the atomic type 'xs:NCName'.
simple.xsd:46: element attribute: Schemas parser error : Element '{http://www.w3.org/2001/XMLSchema}attribute', attribute 'name': 'dmd:surveyId' is not a valid value of the atomic type 'xs:NCName'.
simple.xsd:50: element element: Schemas parser error : Element '{http://www.w3.org/2001/XMLSchema}complexType': The content is not valid. Expected is (annotation?, (simpleContent | complexContent | ((group | all | choice | sequence)?, ((attribute | attributeGroup)*, anyAttribute?)))).
WXS schema simple.xsd failed to compile

I think it has something to do with the namespaced attributes.