Trying to use function format-dateTime, but it is throwing " Unable to perform XSL transformjavax.xml.transform.TransformerConfigurationException: Error checking type of the expression 'funcall(format-dateTime, [step("child", 34), literal-expr([Y0001][M01][D01]T[H01][m01][s01].000 GMT)])'. " error.
The underlying class is normally in the relevant jre jars, which are provided by the application server vendors. What is your underlying platform? If you can show us the complete error stack, we may be able to guide you through.