This page is in a suite of pages testing how search indexers do with page modification dates. If the server is resetting the dates dynamically, adding HTTP Equiv tags can identify the meaningful content date.
<meta http-equiv="Last-Modified" content="01 May 2005 01:00:00 GMT">
Not all search engines will honor these tags, but they ought to!
SSI include of actual Modification Date:
Thursday, 05-May-2005 00:00:00 EDT
Search Code: RTest, RTest264, RTestGood, RTestGood264
For more tests, see the Date Test Suite and the List of Search Indexing and Robot Tests.