Emailing threading grouping by subject even though completely separate threads

[mike.harris.kcp at gmail.com]

If there is a email thread with the same subject it groups any email that has 
the same subject.

I have 2 emails from 2 separate people that have the same subject sent on very 
different days (weeks difference) but they group under the same thread because 
the subjects match.

The threading should group based not only on subject but the headers of who 
it's to/from/cc'd on

not a wildcard subject match

-- 
Best Regards,
Mike Harris