Variables in banners

Sometimes it is handy to display the name of the device, the line number you are connected to or other details about a device in the banner. A complete list of the variables (and which banners they can be used in) is available in the Cisco document Slip-PPP and Banner Tokens.
I thought it would be handy to use those tokens in the name of the file for the archive command.... unfortunately it doesn't work. If you use:
archive
   log config
      hidekeys
   path tftp://192.168.1.1/$(hostname)
   write-memory
   time-period 86400

All you end up with is a file called $(hostname)-0 on your tftp server. Hopefully it will be there in a future release.