Getting information from the user after Access policy has run completely?

Is it possible to get info from the user after access policy has run through completely?

 

Example: I have an access policy that presents a user with a portal access resource among other things. The portal access resource type is an application uri. The host name of the target computer is in the uri. I want to be able to prompt a user, after he/she has clicked on the application resource, to input the host they want to connect to, and then have the F5 update the URI with that information. The users regularly stand up and take down hosts, so keeping a static list of hosts would not be practical.

 

I attempted to create both an irule and ilx with an access_acl_allowed event, but couldnt find a way to present the user with a pop up window to get that info.

 

I also attempted to figure out if there was a way to maybe re-run a macro within the access policy or another access policy altogether to get the info, but had no luck.