Dynamic Role Assignment

Hi,

I have integrated one web application to portal using Application Integrator and provided the SSO. Created the iView and displayed to all portal users. Now requirement is like only authorized users should see this iView. I am aware of role based access provided by portal but in my case roles are not defined in ldap. Roles will be in web application. So authorization will happen in web application end. So when web application says that this user is not authorized, we should not display that iview to that particular user.

Can somebody suggest me that is this possible in portal?

Thanks in advance.

Manish