Policy References using query string

Hi all. 
 
I need some help with my policy reference file. In our case we have an
application that is used by a number of clients and configured according
to their requirements (its an online banking system). However, for
reasons that are not important, the only thing that distinguishes
between the different clients is part of the query string. 
 
What I want to know is whether the following is a valid way to build a
my policy references file:
 
<META xmlns="http://www.w3.org/2002/01/P3Pv1">
 <POLICY-REFERENCES>
  <EXPIRY max-age="172800"/>
    <POLICY-REF about="/P3P/MyCU.xml#first">
      <INCLUDE>/*?*inst=/bc/mycu*</INCLUDE>
    </POLICY-REF>
    <POLICY-REF about="/P3P/MyOtherCU.xml#first">
      <INCLUDE>/*?*inst=/ab/myothercu*</INCLUDE>
    </POLICY-REF>
 
 </POLICY-REFERENCES>
</META>
 
 
Thanks

H. Adam van den Hoven

Web Developer

Credit Union Central of BC