XML Canonicalizer from IBM's XML Security Suite: http://www.alphaworks.ibm.com/tech/xmlsecuritysuite
C14nDOM reads an XML document from stdin and writes the canonicalized output to stdout:
% java C14nDOM -xpath < hotcop.xml > canonicalized_hotcop.xml
-xpath option necessary to support October 26, 2000 working draft and later versions.