-- platform:
Gateway 6.13.0 SP1 on linux-x86-32
Secure Relay RA 2.1.3 on a different linux-x86-32

-- an FTP transfer to a remote server through RA fails with:
NET072E    22.10.2010  10:41:06  Client(8) SecureRelay failed to process request (Error creating connector to /10.0.0.37:1770: java.net.UnknownHostException: dmzhost: dmzhost).

-- dmzhost is the hostname of the machine where Secure Relay RA is installed and 10.0.0.37 is the IP of the FTP server
-- the Linux host name is usually configured in the network configuration and sometimes may not  be added in the hosts file

The hosts file on the Secure Relay RA machine should contain the ip/hostname association of the RA's AdminInterface and the hostname

-- on the Secure Relay RA machine add in the hosts file the following line:

<RA_IP>   dmzhost

-- for example:

127.0.0.1 localhost
10.100.20.200   dmzhost

-- Stop Gateway and Secure Relay RA in this order
-- Start Secure Relay RA and Gateway in this order