Ok
Customizing firewall rules:
http://www.symantec.com/business/support/index?page=content&id=HOWTO80816&actp=search&viewlocale=en_US&searchid=1361790569650
setup firewall rules;
http://www.symantec.com/business/support/index?page=content&id=HOWTO80979&actp=search&viewlocale=en_US&searchid=1361790569650
Adding a new firewall rule:
http://www.symantec.com/business/support/index?page=content&id=HOWTO81156&actp=search&viewlocale=en_US&searchid=1361790569650