How do I configure certificate as part of request?

I have already tried those steps in http://geekswithblogs.net/gvdmaaden/archive/2011/02/24/how-to-configure-soapui-with-client-certificate-authentication.aspx

but it didn't seem to be considering my cert in the Preferences.  I have also tried giving my cert path in the SSL Keystore property of the Request but it also didn't work.

I'm getting the below generic error from the service which indicates my request didn't contain the cert with it.

The message could not be processed. This is most likely because the action 'http://tempuri.org/.......' is incorrect or because the message contains an invalid or expired security context token or because there is a mismatch between bindings. The security context token would be invalid if the service aborted the channel due to inactivity. To prevent the service from aborting idle sessions prematurely increase the Receive timeout on the service endpoint's binding.