From Sven Van Caekenberghe:

Recently, I moved and renamed 3 of my open-source Common Lisp projects to common-lisp.net:

S-XML (http://common-lisp.net/project/s-xml) is a simple, basic XML parser for Common Lisp with both a pure functional, (S)SAX like event interface as well as a DOM interface with LXML, SXML and an XML-ELEMENT struct DOM representation. Rudi Schlatte and Brian Mastenbrook are co-developers/maintainers.

S-XML-RPC (http://common-lisp.net/project/s-xml-rpc) is an implementation of the XML-RPC protocol in Common Lisp for both client and server. Rudi Schlatte and Brian Mastenbrook are co-developers/maintainers and added porting to SBCL. Rudi Schlatte added a number of XML-RPC extensions recently.

CL-PREVALENCE (http://common-lisp.net/project/cl-prevalence) is an implementation in Common Lisp of the Object Prevalence concept using both XML and s-expression based serialization. Thanks to testing by Bill Clementson, ACL and Windows are now supported too.

All projects use ASDF and should be ASDF-INSTALL-able. As for all common-lisp.net projects, there is CVS access and there are mailing lists. All code runs on multiple CL implementations.