Ah, I have a perhaps better solution:
Create an SQL data source with credentials to the Mango database, then create a point that updates tables only with SQL like the following,
update events set message=? where id=(select id from events where typeName='DATA_POINT' and typeRef1=? and typeRef2=? order by id desc limit 1);
and parameters like,
then create a set point handler from the event in question to this SQL point, and add the original point that raised the event into the set point hander's script context. Our script will look like,
return "('common.default|Point value changed to " + p.value + "|'," +
event.getReferenceId1() + "," + event.getReferenceId2() + ")";
'common.default' is a translation key for literals. The format of the message column appears to be messageKey|arg1|arg2|arg3|...| so I'm setting the message to
"Point value changed to " + p.value in this example.
If necessary, I can demonstrate it with the script on the email handler, then you could also set the subject line from there and it'll all be consistent (if you're emailing it too).