ReST API - 401 SecurityContext exception

Hi Everyone,

I just tried to GET reposonse for the following ReST API

http://xxx:8080/qcbin/rest/domains/DEFAULT/projects/QCDemo/defects/174

through SOAP UI Pro tool but it thorws the following exception

HTTP Status 401 - An Authentication object was not found in the SecurityContext

type Status report

message An Authentication object was not found in the SecurityContext

description This request requires HTTP authentication (An Authentication object was not found in the SecurityContext).
JBoss Web/2.1.3.GA

Also i tried the Login ReST API call [http://xxx:8080/qcbin/rest/is-authenticated?login-form-required=y] via SOAP UI but it request the user to manually enter the login login credentials. 

Even after provided the login details got only the below response and didn't find any session_id or LWSSO ids.

<AuthenticationInfo>
<Username>testuser</Username>
</AuthenticationInfo>

Pls help me if there is anyway to do it.

Thanks,

Hari