AsymmetricBinding validation without IncludeTimestamp doesn't work

AsymmetricBinding validation without IncludeTimestamp doesn't work with the error:

Original Exception was org.apache.wss4j.policy.WSSPolicyException: Assertion

{http://docs.oasis-open.org/ws-sx/ws-securitypolicy/200702}

X509Token not satisfied

It appears that the Initiator X.509 Token (which is included in the request) is only marked as a SupportingToken, and hence does not get asserted. Adding in an IncludeTimestamp policy makes the test pass.