namingContexts

[Eithne Holmes <EithneH@VISIO.COM>]

Hi,
NamingContexts (top level) attribute is defined as follows :
5.2.1 namingContexts 
	The values of this attribute correspond to naming contexts which
this server masters or shadows. If the server does not master any
information (e.g. it is an LDAP gateway to a public X.500 directory) this
attribute will be absent. If the server believes it contains the entire
directory, the attribute will have a single value, and that value will be
the empty string (indicating the null DN of the root). This attribute will
allow a client to choose suitable base objects for searching when it has
contacted a server. 

I can't figure in what case there's likely to be only a single empty string
value, as the current domain name at least seems to always be returned.  If
the empty string (null DN) were returned would it suffice as the base object
parameter in the search function ?    Searching on the null DN only returns
server attribute info and no children in any scenario I've come across
(talking to Netscape Directory server).
Thanks,
Eithne