Setup

 breakpad=> select id from reports where product = 'Firefox' and version = '4.0b12' limit 10;
     id
 -----------
  225058458
  225056101
  225009974
  224715201
  224715184
  224715172
  224715122
  224715112
  224715109
  224715066
 (10 rows)
 breakpad=> update reports set signature='test1', email =  where id in (select id from reports where product = 'Firefox' and version = '4.0b12' limit 10);
 UPDATE 10
 breakpad=> update reports set email = '(test email 1...)' where id = '225058458';
 UPDATE 1

Repeat above, inserting 4 unique test emails throughout 10 crashes.

 breakpad=> select min(date_processed),max(date_processed) from reports where signature='test1';
             min             |            max
 ----------------------------+----------------------------
  2011-02-25 12:59:43.272192 | 2011-02-27 23:58:31.428362
 (1 row)

QA Test

Campaign creation

 https://crash-stats.stage.mozilla.com/admin/email
 Product: Firefox
 Exact Signature: test1
 Version: 4.0b12
 Start Date: 25/02/2011
 End Date: 01/03/2011
 Clicked Next
 Confirm Email                           
 Sending this email will contact 4           Firefox 4.0b12 users who crashed on test1           between 25/02/2011 and 01/03/2011
          
 Subject:
 anything goes
          
 Email Body:
 Paste Email Message here.
 *|UNSUBSCRIBE_URL|*
         
 Note: Email template variables are displayed above, don't worry they will be             replaced in the actual email.
         
 Note: The number of contacts above is an estimate. We won't email            a user who has already been contacted about Firefox's             test1 crash. Malformed email addresses may also inflate the estimate.            The estimate is higher or the same as            the actual number of email addresses that will be contacted, if you choose to continue.