SoapUI adding Truststore is giving KeyStoreException: No private keys found in keystore!

I have been trying to add a truststore which contains only public certificates and no private keys. It needs a password to manage it of course, but viewing the included public certificates can be done without the need of a password. The format used is jceks. Whenever I try to add the truststore in SoapUI, I get the "KeyStoreException: No private keys found in keystore!" Why would SoapUI be expecting private keys in the truststore? Also the exception is preventing me from selecting it within the wss policy configuration.