Looking for standalone DTD/CSS/... validator

[Manuel Collado]

I'm trying to find command-line, stand-alone utilities that let me
validate a variety of XML related stuff. Like:

- validate a DTD file (the DTD itself, not an XML document)
- validate a CSS2 style sheet
- etc.

I'm looking for utilities similar to a compiler, that give messages with
reference to the line (and column) of the offending element, e.g.:

some.dtd:14:7: Expected '<!'
some.dtd: Undefined element 'Example'

Stand-alone utilities are preferred (no Java or other fat runtime
support dependent). So far I've only found:

- csslint (part of libcroco)
- xmllint (part of libxml2)
- dtdvalid (part of XMLmind XML editor, in Java)
- CSS2 validator (from W3C, in Java)

Does anybody know other things to try?

Thanks,