How to add a seperator or line in CustomAction Menu

<customaction id="UserInterfaceCustomActions.DocLibActionsToolbar">
                RegistrationType="List"
                RegistrationId="101"
                Rights="ManageWeb"
                GroupId="ActionsMenu"
                Location="Microsoft.SharePoint.StandardMenu"
                Sequence="1000"
                Title="Analyse Document"
                Description="Analyse file(s)/folder(s) in this library"
                ImageUrl="/_layouts/images/FRXImages/FRXFile_Detector.gif">
    <urlaction url="_layouts/FRXFileLength.aspx?List={ListId}" />
  </customaction>
  
Thanks, 
Krishna