Is the Host where you run the command in the same subnet (and not firewall active) as the ESX host? In my case this was the problem, the documentation says that vmrun needs to connect to port 443 of the host/VC server, but i found out that for some commands (vmrun ... suspend <PathToVMXFile> in my case) the communication goes from the machine where vmrun was issued directly to the ESX host to some port (i assume 8443) and to the VC-Server on port 443.
Does this solve your issue?
