You should always try to get dates in yyyy-mm-dd format. This is
unambiguous and should always be translated correctly.

Your comment

> A problem  arises, however, because the
> date  in the web  query table is sometimes
> of the above format, and sometimes in the
> format  01/21/2008.

is a concern, though. Why would the query  return dates in different
formats? You need to sort out the input (query) first, otherwise you are
risking a GIGO situation.