def value
			if @value
				matches = @value.scan(PEREFERENCE_RE)
				rv = @value.clone
				if @parent
					matches.each do |entity_reference|
						entity_value = @parent.entity( entity_reference[0] )
						rv.gsub!( /%#{entity_reference};/um, entity_value )
					end
				end
				return rv
			end
			nil
		end
def value
			if @value
				matches = @value.scan(PEREFERENCE_RE)
				rv = @value.clone
				if @parent
					matches.each do |entity_reference|
						entity_value = @parent.entity( entity_reference[0] )
						rv.gsub!( /%#{entity_reference};/um, entity_value )
					end
				end
				return rv
			end
			nil
		end
Returns the value of this entity.  At the moment, only internal entities
 are processed.  If the value contains internal references (IE,
 %blah;), those are replaced with their values.  IE, if the doctype
 contains:
  <!ENTITY % foo "bar">
  <!ENTITY yada "nanoo %foo; nanoo>
 then:
  doctype.entity('yada').value   #-> "nanoo bar nanoo"