Do you do something like this:

Session("Rola1") = "Admin|User"

And if you want to see if the session variable has a perticular value, you cand do it this way:

If Session("Rola1") IsNot Nothing
   If InStr(Session("Rola1"), "Admin") > 0
      ' True
   Else
      ' False
   End If
End If

Hope this helps