When managing an ESX4.0x Host using the vSphere 4.1 Client via vCenter you are unable to add vmnic's to vSwitches.
From the Configuration Tab select Networking.
Select a Virtual Switch, i.e. vSwitch 0 and click Properties
on the vSwitch Properties window select the Network Adapters Tab
Click the Add Button, and a new window is not spawned as expected.
This is repeatable on ESX 4.0 Update 2, ESXi 4.0 Update 2, ESX 4.0 Update 1. I have not been able to test it on ESXi 4.0 Update 1 it is most likely to occur.
To work around this issue connect the vSphere client directly to the ESX/ESXi host. Follow the steps above and a new window will open to allow the selection of vmnics'.
