Powershell SMO work in cmd, not from script

This was originally posted (incorrectly) in the SMO/RDO/DMO forum. Sorry.My code (Server 2003 Enterprise, SQL Server 10.0.5512.0, Powershell v1.0 ISE) is as follows:function Script-Database_01 {# Created: 09/06/2013# Edited: 09/06/2013[CmdletBinding()]param([Parameter(Mandatory=$true,ValueFromPipeline=$true,HelpMessage="Local directory to save build-scripts output.")][Alias('fp')][string[]] $Filepath,[Parameter(Mandatory=$true,ValueFromPipeline=$true,HelpMessage ="Server or instance name.")][Alias('ds')][string[]] $DataSource,[Parameter(Mandatory=$true,ValueFromPipeline=$true,HelpMessage="The database to be scripted.")]#[Alias('db')][string[]] $DatabaseName)BEGIN{Write-Output $FilepathWrite-Output $DataSourceWrite-Output $DatabaseNameGet-PSSession}PROCESS{# Set 'Option Explicit' to catch subtle errors:set-psdebug -strict#Load SMO assembly, and SMOExtended and SQLWMIManagement libraries:$ms = "Microsoft.SqlServer"$v = [System.Reflection.Assembly]::LoadWithPartialName("$ms.SMO")[System.Reflection.Assembly]::LoadWIthPartialName("$ms.SMOExtended") | out-null$my = "$ms.Management.SMO"$source = new-object("$my.Server") $DataSourceif ($Source.Version -eq $null) {Throw "Cant find the instance $DataSource."}$db = $source.Databases[$DatabaseName]if ($db.name -ne $DatabaseName) {Throw "Cant find the database '$DatabaseName' in $DataSource."}$transfer = new-object("$my.Transfer") $db$transfer.Options.ScriptBatchTerminator = $true # This only goes to file$transfer.Options.ToFileOnly = $true # This only goes to file$transfer.Options.Filename = "$($Filepath)\$($DatabaseName)_Build_01b.sql"# Do it:$transfer.ScriptTransfer()}END{}}When I execute everything in the PROCESS{} section, the commands succeed, and the file is correctly output. When I run the script (as .\Script-Database_01.psq [+parameters] I get the follow error:New-Object : Cannot find an overload for "Server" and the argument count: "2".At C:\Powershell\Scripts\Script-Database_01.ps1:44 char:29+ $source = new-object <<<< ("$my.Server") $DataSource+ CategoryInfo : InvalidOperation: (:) [New-Object], MethodException+ FullyQualifiedErrorId : ConstructorInvokedThrowException,Microsoft.PowerShell.Commands.NewObjectCommandI assume this has something to do with the import of SMOExtended, but I can't see it.Can anyone point me in the "write" direction?