How to use Outlook Redemption to send mail attachment from Powerbuilder

Here is an example of code that I am using to send mail via outlook redemption in my application.  This is tested / working code.  My question is how is it that I may add an attachment to this email?  My initial thoughts were:
oleSafeMailItem.Attachments.Add = ls_filename
However, this is not correct.  Can someone please point me in the right direction?

Example:
 oleOutlook = create oleobject
     rc = oleOutlook.ConnectToNewObject("outlook.application")
     
     If rc = 0 Then
          oleNameSpace = oleOutlook.GetNameSpace("MAPI")
          oleNameSpace.Logon("", "", true, true)

          oleSafeMailItem = create oleobject
          rc = oleSafeMailItem.ConnectToNewObject("Redemption.SafeMailItem")

          If rc = 0 Then
               oleTmp = create oleobject
               oleTmp = oleOutlook.CreateItem(0)
               oleSafeMailItem.Item = oleTmp
               oleSafeMailItem.Recipients.Add(ls_sendto)
               oleSafeMailItem.Recipients.ResolveAll
               oleSafeMailItem.Subject = ls_subject
               oleSafeMailItem.Send

          Else
               MessageBox("Mail Error", &
                       "Your email could not be sent.  Please contact IT.~r~n" + &
                       "The SafeMailItem  - ConnectToNewObject~r~n" + &
                       "failed with a return code of " + String(rc) + ".", &
                       StopSign!, &
                       Ok!)
          End If
     Else
          MessageBox("Mail Error", &
                  "Your email could not be sent.  Please contact IT.~r~n" + &
                  "The Outlook Application  - ConnectToNewObject~r~n" + &
                  "failed with a return code of " + String(rc) + ".", &
                  StopSign!, &
                  Ok!)
     End If

Regards,
Kristi