Eclipse (at least Juno) will complain that there is “No grammar constraints (DTD or XML Schema) referenced in the document.”, even though there is no DTD for Ant build.xml files (see here for Ant faq about DTD for build.xml files).
To surpress the warning in Eclipse add
After the <?xml . . . XML declaration tag → Continue reading “How To Disable the DTD Warning for Ant build.xml Files in Eclipse”