A handy addition in XSLT 2.0 is a nice set of date and time format XPath functions. XSLT 1.0 was decidedly lacking in these functions, so you may have used a third-party library such as EXSLT for this purpose. EXSLT offers arithmetic functions on dates and times (still absent in XSLT 2.0) but the XSLT 2.0 offering is...