Feature request: Per-subnet Passive IPs for server

[CodeCat]

I've been using FZ Server for a while now and I like it. But one point where I ran into trouble is getting PASV mode to work in combination with SSL. I'm not the only one with this problem, apparently: http://filezilla.sourceforge.net/forum/ ... .php?t=894

I'm on a LAN behind an NAT router. Normally, I just leave my passive IP address on default, and the router automatically picks up the response the server sends to the PASV command and translates my internal IP to my external one. But, when I use SSL that doesn't work anymore, because the encryption means the router can't read nor translate the message anymore. It's not able to get past the encryption. So the client ends up connecting to 192.168.x.x which is obviously not going to work.

So what I'd really like to see to fix this and related problems is to be able to set a different PASV mode IP for each IP subnet. For example:
192.168.0.0 / 16 -> my internal IP:port range 1
All others -> my external IP:port range 2

Could that be implemented?