Boost XSLT with Extension Objects

XSLT is my favourite language when developing web application, thought XSLT does not contain all the power found in languages such as C# or VB.NET. In situations where you need to perform functions that XSLT cannot handle in its own, you can resort to XSLT extension objects.

I have been working last months on group calendaring application and there I have face huge problems with dates. How to format dates on XSLT? Version 1.0 of XSLT doesn?t support sorting dates using the xsl:sort tag. This can present a problem since dates frequently play an important role in my calendar application. Now I just need to figured out how this one work. ?