How to show a Legal Notice when users log onto the network

I am able to add a legal notice to users desktops by modifying the following registry keys:
- HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system\legalnoticecaption
- HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system\legalnoticetext

The problem I have is rather than manually applying this to each desktop, I want to find a way to automatically set this via a login script, group policy, etc so I can get the legal notice applied to 100+ systems on the network. I am running a Windows 2003 server domain.  

I've researched how to do this on E.E. and have tried the following:
1) Apply the following commands to the login script:
reg add "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon /v LegalNoticeText /d "I put the heading text to be displayed here" /f
reg add "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon /v LegalNoticeCaption /d "I put the message to be displayed here" /f

When I try this from the command line I get the following error:
Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.

C:\Program Files\Windows Resource Kits\Tools>reg add "HKEY_LOCAL_MACHINE\SOFTWAR
E\Microsoft\Windows NT\CurrentVersion\Winlogon /v LegalNoticeText /d "I put the
heading text to be displayed here" /f

Error:  Too many command-line parameters

C:\Program Files\Windows Resource Kits\Tools>


2) I created a logonmessage.vbs file as follows:

Option Explicit
 
' Constants
Const HKEY_LOCAL_MACHINE = &H80000002
 
' Variable Declarations
Dim strComputer
Dim objReg
Dim strKeyPath
Dim strValueName
Dim strValue
 
' Variable Initialisations
strComputer = "."
Set objReg = GetObject("winmgmts:\\" & strComputer & "\root\default:StdRegProv")
strKeyPath = "SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon"
 
' Construct the LegalNoticeCaption and set the value
strValueName = "LegalNoticeCaption"
strValue = "I put the heading text to be displayed here"
objReg.SetStringValue HKEY_LOCAL_MACHINE, strKeyPath, strValueName, strValue
 
' Construct the LegalNoticeText and set the value
strValueName = "LegalNoticeText"
strValue = "I put the message to be displayed here"
objReg.SetStringValue HKEY_LOCAL_MACHINE, strKeyPath, strValueName, strValue
 
' Tidy up and quit
Set objReg = Nothing
WScript.Quit


I am still new to using VB scripts - so I'm not sure if I am running the above code correctly.  When I run the above vb script I do not see any errors, but when I go into the registry I do not see the LegalNoticeCaption and LegalNoticeText keys updated.  

Any help you can provide would be greatly appreciated.  Thank you in advance.