XMLToaster is a tool for extracting and loading XML from databases. It provides a modified version of SQL which has XML mapping extenstions. It can be compared to the "for xml" command in MS SQL Server 2008, but it runs on all common databases and scales to handle very large XML mappings without too much complexity. It is used as a Java library to write XML interfaces, but can also be run as a command line tool.
The runtime is now Java 5 and you may now specify a namespace for an XML message that does not have an associated XSD.