I have two notebook, one act as a gateway to the internet and the other is a client.
1st computer connected to the internet using HSDPA Modem, and i connect the 2nd computer using ethernet cable...no hub/switch/router between them,..just a simple direct cable between 2 notebook.
Here's the scheme :
HSDPA Modem (internet) -> 1st Computer -> Ethernet Cable -> 2nd Computer
Before using BDIS 2009, everything went fine..
but bitdefender firewall is somehow blocking internet access in 2nd computer.
I try to make the trust level on ethernet card adapter to "full trust" but it's not working.
Making the stealth mode is off..not working either..
Before you ask,..yes..i already enabling ICS option in bitdefender firewall advance setting.
And i goes all the way to make BDIS goes to Gamer Mode (in both computer),..nothing happened.
I even disabled firewall in BDIS 2009 in both computer,..but nothing happened either.
I try also using bluetooth as my ICS device, but is not working.
So it's not an ethernet issue (i think).
The only thing that make ICS work is uninstalling BDIS 2009 in the first computer. But that's not a solution.. 
I have try every possible way i can think of, but hey i'm not an expert maybe i've missed some step though...
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My Spec on both computer pretty much the same :
Intel Centrino Duo 1,85 Ghz
Windows XP SP2
1 GB RAM
Wifi
Bluetooth
Ethernet Card
And both using BDIS 2009 v12.0.11.2
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Truth is...i never encounter such a problem using various Internet Security Suite before,..bitdefender is my first encounter...
After some fatal False Positive from bitdefender,..now this ??? In my first day using bitdefender...Oh man.. 
Any help will be appreciate.
Thanks.