Antenna House developed PDF5-ML as an open source plug-in for the DITA Open Toolkit used to produce PDFs with XSL Formatter as the formatting engine. It is intended to replace PDF2; the default PDF transformation plugin provided with the DITA-OT.
The PDF5-ML plugin simplifies PDF output customization w/ a main XML file and subsequent XML files for each language. The main XML file contains the most commonly used style properties and is easy to read. Style can also be dynamically applied by function call.
PDF5-ML is designed to work w/ i18n index library and Formatter, which provides multilingual back of the book indexing and output to various PDF formats. Applying style by language is made easy, simply add your language file.
DITA PDF Solution = Formatter + PDF5-ML Plugin + I18N Index Library