FTP/Rename-ItemFTP.ps1

function Rename-ItemFTP {
    Param(
        # existing path of the item to rename
        [Parameter(Mandatory=$true)]
        [string]
        $OldPath,
        # name of the item to rename
        [Parameter(Mandatory=$true)]
        [string]
        $Name,
        # new path to rename the item to
        [Parameter(Mandatory=$true)]
        [string]
        $NewPath
    )

    $FtpScript = Split-PathToFTPScript $OldPath
    $FtpScript += "rename `"$Name`" `"$NewPath/$Name`""
    Invoke-FTP $FtpScript
}

Export-ModuleMember -Function Rename-ItemFTP