IcaEnableKeepAlive doesn't work

[DFRA603]

Customers that connect via Internet are disconnected after 1 hour of inactivity (because of firewall)
During this hour there isn’t a single bit transferred to the client (monitored with a sniffer)
I tried implementing IcaKeepAlive but that doesn’t seem to work. This is what I did:

On the Windows 2000 terminal server I installed SP2
I had to add ??? the value HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Citrix\IcaEnableKeepAlive (The documentation says it should be present!)
I also added the KeepAlive timeout settings in the TCP/IP settings.
Rebooted the server

What is going on ???

 

[CitrixEngineer]

Was the documentation you read for NT TSE? This key does not exist in the Windows 2000 installation of Metaframe.

Is it just the Citrix session or the entire connection that is dropped? If it's the connection, then it's probably down to your ISP.

Hope this helps