You want to use dates that are outside the range of what a 32-bit epoch timestamp can handle: roughly before 1901 or after 2038.
Use the PEAR Date_Calc class, which can handle dates from January 1, 1 CE to December 31, 9999 CE. Example 3-45 prints formatted dates for two days in the 9th century CE.
Example 3-45 prints:
Benjamin Franklin died on Saturday April 17, 1790.
Because Date_Calc uses its own internal representation for dates, it's not subject to the limits of storing an epoch timestamp in a 32-bit integer. Its dateFormat( ) method works similarly to strftime( )'it turns a format string into a formatted date and time string. Table 3-7 lists the formatting characters that dateFormat( ) understands.
Date_Calc makes it easy to work with a wide range of Gregorian calendar dates, but it does not have comprehensive knowledge of the religious, political, and cultural factors that have caused modification to the calendar over time.
3.16.4. See Also
The PEAR Date package at http://pear.php.net/package/Date. The tip of the calendar-changing-over-time-wackiness iceberg is explored at http://en.wikipedia.org/wiki/Old_Style_and_New_Style_dates.