Duplicate "Subject:" line in some tickets

I recently upgraded RT from 3.6.6 -> 3.8 -> 4.2.7 and I’ve noticed that
some (it seems to be new) tickets have two “Subject:” lines in them. For
example, when looking at the full headers for a message, I see:

These same duplicate headers appear in the web UI. Could this be a bug
with ticket creation?

Thanks,

Please don’t CC both rt-users and rt-devel, pick one.On Wed, Sep 17, 2014 at 02:07:09PM -0700, Brian McNally wrote:

I recently upgraded RT from 3.6.6 -> 3.8 -> 4.2.7 and I’ve noticed that some
(it seems to be new) tickets have two “Subject:” lines in them. For example,
when looking at the full headers for a message, I see:

Subject: Re: [GS #58207] This is a test ticket
Subject: Re: [GS #58207] This is a test ticket

These same duplicate headers appear in the web UI. Could this be a bug with
ticket creation?

All tickets or some tickets?
How are the tickets created?
What customizations / plugins do you have?
Are you using HTML templates?
Please show some full headers.

-kevin