You can only use CDO/MAPI under Exchange 2003. Not a lot of example exist, but check there: HOW TO:Set folder level permissions using CDO 1.21 and ACL.dll
Does it work good, no idea (but it's from microsot's blog and wrote by an microsoft employee)
Edited: To create folder, a CDO example:https://msdn.microsoft.com/en-us/library/ms878640(v=exchg.65).aspx
The following examples show how to create a folder in the Exchange store. The function in each example performs the following steps:
The function attempts to create a folder at this URL. If an error occurs, the function fails.
If the function is successful, it sets the new folder's contentclass Field to the value "urn:content-classes:folder".
The function returns a reference to the Record object that is bound to the new folder.
VBScript
If WScript.Arguments.Count < 1 Then
WScript.Echo "Usage: cscript createfolder.wsf URL [content class]"
WScript.Quit
End If
Dim sUrl
Dim sContentClass
' Note: It is recommended that all input parameters be validated when they are
' first obtained from the user or user interface.
sUrl = WScript.Arguments(0)
sContentClass = WScript.Arguments(1)
Dim Rec
Wscript.Echo "Creating folder at URL: " & sUrl
Set Rec = CreateFolder(sUrl, sContentClass, Nothing)
Wscript.Echo "Succeeded."
Function CreateFolder( sUrl, sContentClass, Conn )
Dim Rec
Set Rec = CreateObject("ADODB.Record")
' Did caller pass a Connection object reference?
If Not ( VarType(Conn) = vbObject AND TypeName(Conn) = "Connection" ) Then
Set Conn = CreateObject("ADODB.Connection")
Conn.Provider = "ExOLEDB.DataSource"
Conn.Open sUrl
End If
If sContentClass = "" Then
sContentClass = "urn:content-classes:folder" ' The Default is urn:content-classes:folder.
End If
' Try to create the folder
Rec.Open sUrl, Conn, adModeReadWrite, adCreateCollection
Rec.Fields("DAV:contentclass") = sContentClass
Rec.Fields.Update
Set CreateFolder = Rec
End Function
EWS can change folder ACL but Exchange 2003 does not support it. You need atleast Exchange 2007.
Set-MailboxFolderPermission can too, but againt it's not available in 2003.
Some example, there and there