hi manni

take a look at these links ...might help

Diggin Em Walls Part 1, 2 and 3

http://www.fromadia.com/categoryread.php?catid=16

Bypassing Firewalls: Tools and Techniques

http://www.first.org/events/progconf/2000/D3-07.pdf

Techniques used for bypassing firewall systems

http://www.terena.nl/tech/task-forces/tf-c...g-firewalls.pdf

Try this
BackStealth is executed within the memory space allocated to your Firewall and thus does not appear to be a separate process. Such "Stealth" technique gives it full rights for access to the web, completely transparent and independant from all other applications.
Personal Firewall Supported:
Kerio Personal Firewall
McAfee Personal Firewall
Norton Internet Security 2002
Sygate Personal Firewall Pro
Tiny Personal Firewall
It connects to: <http://www.pc-facile.com/security/backstealth.txt> and downloads the file saving it as: C:\retrieve.dat
The utility will have no problem at all in accessing the web without any filter being applied from the firewall.
The user, monitoring open connections will notice that the action seems to be carried out by the firewall itself!
HOMEPAGE:
http://edu.supereva.it/piorio/backstealth.htm?p
Also search google lots of such tools and ways are available for bypassing firewalls.
Wish u success.