Thanks Jessica for a good suggestion.
It does not solve my academic question and it is also not usable because my servlet container, Macromedia's JRun, does not support the specs required for the error page functionality.
And, "L" (a name not in keeping with the JavaRanch custom by the way). Here's a code snippet. I hope it formats correctly and is readable.
[ May 31, 2002: Message edited by: Sanjay Anand ]