The Gnome Project has released version 2.6.12 of libxml2, the open source XML C library for Gnome. This release improves W3C schema support, the Python bindings, and the command line tools. They also fixed some bugs. They've also released version 1.1.9 of libxslt, the GNOME XSLT library for C and C++. This is a bug fix release.
Mikhail Grushinskiy has posted XMLStarlet 0.93, a command line utility for Linux that exposes a lot of the functionality in libxml and libxslt including validation, pretty printing, and canonicalization. This release has been recompiled against libxml2 2.6.12 and libxslt 1.1.9.
Ian E. Gorman has released GXParse 1.4, a free (LGPL) Java library that sits on top of a SAX parser and provides semi-random access to the XML document. The documentation isn't very clear, but as near as I can tell, it buffers various constructs like elements until their end is seen, rather than dumping pieces on you immediately like SAX does. This release makes various API changes.
Nate Nielsen has released RTFX 0.9.4 (formerly RTFM), an open source (BSD license) tool for converting Rich Text Format (RTF) files into XML. "It majors on keeping meta data like style names, etc... rather than every bit of formatting. This makes it handy for converting RTF documents into a custom XML format (using XSL or an additional processing step)." Version 0.9.4 shoudl be much faster.
Engage Interactive has updated two open source XML parsers written in PHP. SAXY 0.8.5 exposes a SAX like interface. DOMIT! 0.9.6 exposes an API based on the Document Object Model (DOM). Both are published under the GPL. These releases add namespace support and fix bugs. This also means DOM Level 2 is now mostly supported.
The Apache Web Services Project has posted JaxMe 2 0.31, an open source implementation of the Java API for XML Data Binding (JAXB). It also extends JAXB with various features including a persistency layer. However, according to the FAQ, "As of this writing, JaxMe 2 isn't sufficiently mature for large projects."