Configure for Transport Level Security (SSL) on Web Service

Hi,

We are trying to set up SoapUI for testing a webservice that has been protected by SSL, mutual authentication.

There is already a client application that we developed that is able to connect and send-receive messages from it using the same certificates.
Our client is configured and started with the following parameters:
-Djavax.net.ssl.keyStorePassword=<password>
-Djavax.net.ssl.keyStore=goca_99.keystore
-Djavax.net.ssl.keyStoreType=jks
-Djavax.net.ssl.trustStorePassword=<password>
-Djavax.net.ssl.trustStore=goca_99.truststore
-Djavax.net.ssl.trustStoreType=jks

When we try to set up soapUI with the same files, we always get 403 Forbidden back.
* We put the *.keystore file in the Preferences > SSL Settings: Keystore and password and check "requires client authentication".
* We added the *.keystore file and the *.truststore file to the project WS-Security Configurations > Keystores & Truststores...
* We played around with the request property 'SSL Keystore" by selecting the keystore file there as well.

Are there configuration parameters/properties that we forget to set?

Thanks in advance,

TomSe.