Problems using vmrun on ESX3.5

Hopefully a quick question because I'm missing something obvious.

I am running vmrun version 1.12.1 against an ESX 3.5 Server and am getting partial sucess.

If I run:

vmrun -T ESX -h http://{ip Address}/sdk -u root list

I am prompted for the password then it lists the VM's running as follows.

Total running VMs: 3

[ha-datacenter/server:storage2] Client/Client.vmx

""                          ""                     ""

""                          ""                     ""

But when I try to list the snapshots using:

vmrun -T ESX http://{ip Address}/sdk -u root listSnapshots "[ha-datacenter/server:storage2] Client/Client.vmx"

or

vmrun -T ESX http://{ip Address}/sdk -u root listSnapshots "[server:storage2] Client/Client.vmx"

I get the following error.

Error: Cannot open VM: [server:storage2] Client/Client.vmx, There was an error in communication.

Thanks,