advanced session variable for proxy setting

Can an advanced session variable be used to set the client proxy address for a network access tunnel on 6.0.3? My limited testing says no but I'm hoping the answer is YES. Thank you!

 

 

Currently I set an ASV e.g. "user_proxy" then in the client proxy address I put:

 

 

proxy.%session.asv.user_proxy%.domain

 

 

No workee! Thoughts? Workarounds?

 

 

Oh wait. Using a non-qualified name and using the ASV in the default domain might work. . . but of course would not work for a person whose proxy is not in their default DNS domain.