We are about to install a CC4H-4S on a network with variable length subnetting. When the mask 255.255.254.0 is entered the CommPlete server rejects it as being an invalid subnet mask. Is there a work-around for this problem?

You can manually edit the config.rn file and put in the correct netmask. FTP to CC4H, download the config.rn file, edit the file, upload back to the CC4H, reboot CC4H so the new settings can take affect.