How is soapUI able to cheat with one-way ssl?

soapUI is able to perform one-way ssl without having the CA root certificate. How is that possible? We are using an in-house Certificate Authority, and soapUI is able to establish an https connection with a server which is requiring one-way ssl. Other java clients I have are not able to communicate with the Server without having a keystore with the CA root certificate.
I also find soapUI very tolerent when establishing two-way ssl connections , but lets leave that for a differernt post.