Question on Allowing null values iin DTD

Team,

How can I declare that element in DTD allows null values?


I read in one site that we have to use Attributes and use "#IMPLIED" for 
doing this.
Allows NULLS -- Use the ? suffix  --- Declare as #IMPLIED

But I want to allow null values for element?


I know that EMPTY element does not allow values. Then what is the purpose of 
having EMPTY element in DTD? Can this serve my purpose of allowing null 
values?

Thank you for your help

_________________________________________________________________
Don�t just search. Find. Check out the new MSN Search! 
http://search.msn.click-url.com/go/onm00200636ave/direct/01/