VS 2008 : Shut Down The Computer When System Is Locked?

I've noticed that a few download management programs do this, like uTorrent for example, where you can set it to shut down the system when the download(s) complete and I would like to implement this in my app as well.

Right now I'm using

Process.Start("shutdown.exe", "-s -t 05")

which works fine if the user is logged in, but my home computer has the screen saver set to lock the computer in which all my app does is exit but the system doesn't shut down like it does when it's logged in. In uTorrent the system shuts down whether the user is logged in or the system is locked Also I would like to know how to detect if the system is locked or not because if they are logged in I, like uTorrent, would like to prompt the user that the system is about to shut down and give them 30 seconds to cancel it.In addition to

Process.Start("shutdown.exe", "-s -t 05")

I also know about

<DllImport("user32.dll")> _
Public Shared Function ExitWindowsEx(ByVal uFlags As Integer, ByVal dwReason As Integer) As Integer
End Function
Call ExitWindowsEx(1I, 0I) 'Shut Down

but this doesn't shut down the system if it's locked either.