Service to accept unsigned SAML assertion

Question

Hi,

Is it possible to make a WCF service to accept unsigned SAML token as authentication (we don't have a CA for now and a STS to sign it)?
Can someone please guide me how to implement it or where to look and how to transmit that unsigned SAML to the service?

The SAML assertion comes as a string to my proxy service and i need to transmit that string (on transparent level) further to the real service. The real service needs to extract the information from that assertion string, validate, execute and return response.

Thanks in advance,
Adriana