13. The computer program product of claim 12 wherein the program code for scanning applies extended regular expression matching to the content of the document to find all occurrences of all dates in any date format in the document.
12. The computer program product of claim 11 further comprising: a program code for scanning the document for all occurrences of all date in any date format in the document; a program code for disambiguating the format of each of the occurrences; and a program code for creating the canonicalized format for each of the disambiguated occurrences.