When formatDateTime() or formatTime() is used to
format a time using "01" as the format picture for the
hours, minutes, or seconds field, then a zero value is
output as "0" instead of "00".
This is actually consistent with the current XSLT 2.0
specification, which defines these format pictures in
terms of xsl:number; but the spec clearly needs to be
Source code changed (in Numberer_en). Test case