Discussed on roundup-users a while ago -- I 
suggested that in installations like ours which run 
multiple trackers it'd be useful to include the 
tracker name in the Subject line of email sent by 
Roundup.

Richard commented:

--
I won't be able to reliably remove the subject line 
syntax (see below) but I _could_ make it more 
flexible to allow:

  [issue123]
  [Roundup tracker name issue123]

as alternatives achieving the same goal. 
Configuring the email subject line is another issue -
 I'd say that a simple on/off switch enabling the 
tracker name in the subject line as above would be 
sufficient. That means it's just a config variable, 
and that's quite easy to implement and use.
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