VBoxManage controlvm ... savestate returns a wrong error code when failing

[bekks]

When using "VBoxManage controlvm <vmname> savestate" and the command fails, the returned exit code is zero instead of non-zero, as you can see here:

myuser@mybox:~$ VBoxManage controlvm myvmname savestate && echo "Cool." || echo "Not so cool."
VBoxManage: error: Machine in invalid state 2 -- saved
Cool.

Doing the same with the pause argument instead of savestate returns the correct error code but a different message with the same logical content, as can be seen here:

myuser@mybox:~$ VBoxManage controlvm myvmname pause && echo "Cool." || echo "Not so cool."
VBoxManage: error: Invalid machine state: Saved
VBoxManage: error: Details: code VBOX_E_INVALID_VM_STATE (0x80bb0002), component Console, interface IConsole, callee nsISupports
Context: "Pause()" at line 116 of file VBoxManageControlVM.cpp
Not so cool.