2.1.1 [W3C-P3P1.0] Section 18.104.22.168.2, Wildcards in policy reference files
The specification states:
URIs represented in policy reference files MUST be properly escaped, as described in [URI], except: Literal '*'s in URIs MUST be escaped in policy reference files (i.e., they MUST be represented as "%2A"). Any '*' present in a URI within a policy reference file will be taken as representing the asterisk wildcard character. Consequently, P3P user agents MUST properly un-escape a URI given in a policy reference file, according to [URI], before trying to match it against an internally represented URI, but only after recognizing any literal '*' present as the asterisk wildcard character.
All Document Modes (All Versions)
The %2A character reference is not unescaped before matching. For example, "/p3ptest/%2A*" will not match "/p3ptest/**".