RDP iRule needed

So I setup a VIP for people to be able to RDP to a group of nodes behind a VS.

I now and looking to create a irule to support getting the user to a specific node when trying a specific hostname which point to the VS IP.

If this was an http request i would right the rule as follows

when HTTP_REQUEST { if { [HTTP::host] eq "maila-rdp" } { node mimail01a-dvw:0 } { elseif { [HTTP::host] eq "mailb-rdp" } { node mimail01b-dvw:0 } { elseif { [HTTP::host] eq "mailc-rdp" } { node mimail01c-dvw:0 } }

However this will not work when the user is typing this into a RDP console, any suggestions on this. Do i need to call out the port which is 3389.