Comment 5 for bug 165979

I looked up libxml docs and added

xmlThrDefLoadExtDtdDefaultValue (1)

to sp_repr_read_file. This is supposed to set the global
option of reading external DTD subset. It does not work
still, for some reason. Maybe a bug in libxml. One problem
is that we use the old API, xmlParseFile, while there's a
newer one, xmlReadFile, which can be passed the
XML_PARSE_DTDLOAD option. I didn't test it because I have an
old libxml which only has xmlParseFile. Maybe if we switch
to newer libxml and start using xmlReadFile with
XML_PARSE_DTDLOAD the problem will go away. If someone's
motivated enough they can test this, or ask around on the
libxml list.

I'm moving this back to bugs. The sample file is attached.