iRule required to change Citrix ICA IP address.

Just change the line

set vipHost "my.vs.address"

to put the FQDN of the ICA VS in there and you should be fine (You could comment out the line in HTTP_REQUEST that sets it as well... That's not actually needed (Sorry, I left a few old bits in there. I only used it for real for a few weeks).

e.g.

when HTTP_REQUEST {
  HSL::send $icapHSL "$icapLogPrefix: [HTTP::uri]"

  set vipHost "[HTTP::host]"
}

That HTTP_REQUEST is really just debugging, it does nothing useful any more...