Added unit tests to document protocol recommendation: "A cache that passes through requests for methods it does not understand SHOULD invalidate any entities referred to by the Request-URI." http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.10 (Current implementation already does this, but always good to have that captured in an automated acceptance test).
httpcomponents/httpclient/trunk/httpclient-cache/src/test/java/org/apache/http/impl/client/cache/TestProtocolRecommendations.java