creating firewall rule on ISA server

I've got ISA server 2004 installed on a Windows 2003 Server and am
setting up the Firewall Policy / Rules. For the most part, this works
fine. But I've hit a small snag.

I need to establish a rule, (or part of a of rule) that allows some
protocols / ports that are not in the predefined lists that are included
with the ISA server interface. Specifically, I need to add a rule that
permits TCP on port 1026. But I can't see any way to do this.

I've dug around in the interface a fair amount looking for a way to do
this. In the part of the interface where rules are edited it seems to
allow a port (or range of ports) to be specifed, but it insists a
protocol also be listed, which is fine. But the protocol options are not
TCP, or UDP, etc. They are options like DNS, DHCP, PPTP, etc, etc, etc.
Thus specifying a port is meaningless. And it appears there is a hook
(folder) in the inteface to allow "user defined" protocols, but I don't
way to actually access this feature. So, like I said, I way to allow TCP
(or UDP) for a specific port.

Thanks in advance for any help.

B Squared
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