If you wish to use a - as part of a menu item name, you must enclose the name in double quotes. This will only apply if you're editing the ~/GNUstep/Defaults/WMRootMenu file manually, as it is handled properly within WPrefs.
This will work:
(ssh, ("us-gw", EXEC, "Eterm -e ssh us-gw"),This will not:
(ssh, (us-gw, EXEC, "Eterm -e ssh us-gw"),Thanks to Martin Sillence for pointing this out.