Xalan is turning out to be something other than I originally thought. At first glance, I thought it was an Apache Server module. However, this now seems to be incorrect. As best as I can tell, it is a library (in either C++, or Java) that allows one to transform XML into HTML using an XSL style sheet.
In my initial thoughts, it was an actual Apache Server Module that allowed for direct URL access to Transformed documents via the use of Apache’s AddHandler directive or something similar.
If anyone (steve? brad? other brad?) knows anything about this, please do me a favor and let me know if I am on the right track with my line of thought here.