Passing access policy session variables to Form SSO configuration

I have a vendor that want use to do a form port to their server with certain http headers for SSO. So I'm trying to use an access policy with a form sso configuration. One paramter that I have to pass is the current time so I have two questions how do I get the current time and put it into a variable to be used in the form post. How do I reference session variable in the form SSO configuration for the http headers? How would I set a variable getting the current time stamp inside a variable assign in the access policy, I don't know if I'm using the TCL expression correctly?

 

 

I tried directly assigning the variable but it didn't work