query!

Hi all,
  I sent a query few days back and didn't get a good
answer for the same.I think i have'nt expressed it
correctly.I will try to explain it again.
  Take an example of FOAF Vocabulary,
    where a <foaf:person> has some properties like
       <foaf:mbox>,<foaf:img> etc.
 And he gave his namespace as,
           http://xmlns.com/foaf/0.1/
ok,so all the rdf files with foaf tags will be used in
searching applications of some subject like person.
Now my question is , 
    i will use the same namespace (ie).,
       http://xmlns.com/foaf/0.1/
but i will define my own properties for a person.I can
do it right!
And ur search engine will search my file by some
crawling mechamism and searches for a specific
property
of a person which wouldnt be avaliable as it is
defined by me.
So, what is the purpose of writing searching
applications if i cannt restrict the namespaces to be
used.Is there any body governing that?
If not no one sticks to a spec as they define their
terms according to their applications and so their
needs will be satisfied but not a solution for global
applications.
Please clarify this , even now if u cant understand, i
will explain it still more clearly.
But i hope u people got my point.
Thanx for helping,
bye.


		
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