自定义.NET身份验证，成员身份，portlet的配置文件提供程

I am wondering if it is possible to leverage the Authentication, Membership, and/or Profile provider features in .NET to help integrate .NET web apps into my company's enterprise portal. In a nutshell, the portal sends custom header values to any application that is 'behind' the portal for fields like the username, user profile data, and some access rights. One issue that we have with the portal is that we aren't able to leverage many of the .NET apps available on the web because they weren't designed to be "portal aware", primarily to trust that the user has already authenticated.I am wondering if it is possible to leverage th