The resolver is not used when converting a DTD with Trang

If the DTD referes to external resources that are mapped through a catalog the 
conversion fails although a resolver that can handle those resources is 
specified. 

A simple example:

catalog.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE catalog PUBLIC "-//OASIS//DTD XML Catalogs V1.1//EN" 
"http://www.oasis-open.org/committees/entity/release/1.1/catalog.dtd">
<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
  <public publicId="urn:ab" uri="urn_ab.ent"/>
</catalog>

test.dtd
<?xml version="1.0" encoding="UTF-8"?>
<!ELEMENT root (a, b) >

<!ENTITY % ab PUBLIC "urn:ab" "ab.ent">
%ab;

urn_ab.ent
<?xml version="1.0" encoding="UTF-8"?>
<!ELEMENT a (#PCDATA) >
<!ELEMENT b (#PCDATA) >

Original issue reported on code.google.com by georgebina76 on 20 Jan 2011 at 7:13

tksk / jing-trang

The resolver is not used when converting a DTD with Trang #134