routing port (anyconnect kernel panic solved)

Hello everybody. I have a kernel panic when I try to use the Cisco AnyConnect client with Lion(10.7.x). Before Lion(<=10.6.x), all was working ok

This is the set up : iMac + Os X10.6, model cable, Linksys WRT54G firmware 4.21.1.

At Startup, The iMac(home) have a "script" who add a route for fowarding the 6666 port to 5900 (screen sharing)

sudo ipfw add 00100 fwd 127.0.0.1,5900 tcp from any to me dst-port 6666

My university doesn't allow me to go out on 5900 port, so i use the 6666 when I try to reach my mac at home (in screensharing I write xx.xx.xx.xx:6666). From home, if I try to reach my mac at work, I start AnyConnect and after that I do a simple screensharing with the ip of my work mac.

With LION, If this "script" are execute at startup, when I try to use Cisco Anyconnect, I have a Kernel Panic after +- 30 secondes.

If these command are NOT execute.... NO kernel panic when using Cisco AnyConnect (but my work mac cannot connect to my home mac)

My question :

In Lion (10.7 and up), how can I tell the equivalent of the command : sudo ipfw add 00100 fwd 127.0.0.1,5900 tcp from any to me dst-port 6666 ?

or

Can I modify the screen app to listen from 6666 since 5900

or

does my routeur can do the job ?

Tx in advance to all

Have a nice day 🙂