Index: trac/attachment.py
===================================================================
--- trac/attachment.py	(revision 2659)
+++ trac/attachment.py	(working copy)
@@ -26,6 +26,8 @@
 from trac.core import *
 from trac.env import IEnvironmentSetupParticipant
 from trac.mimeview import *
+from trac.Notify import TicketNotifyEmail
+from trac.ticket import Ticket
 from trac.web import IRequestHandler
 from trac.web.chrome import add_link, add_stylesheet, INavigationContributor
 from trac.wiki import IWikiSyntaxProvider
@@ -332,6 +334,13 @@
                 pass # don't worry if there's nothing to replace
             attachment.filename = None
         attachment.insert(filename, upload.file, size)
+        if attachment.parent_type == 'ticket':
+            tn = TicketNotifyEmail(self.env)
+            # before we can do this, we have to get the ticket
+            # that the attachment will modify
+            ticket = Ticket(self.env, tkt_id=attachment.parent_id)
+            tn.notify(ticket, newticket=False, modtime=attachment.time)
+            
 
         # Redirect the user to the newly created attachment
         req.redirect(attachment.href())