tkoelman@xs4all.nl (Tom Koelman) writes:

> Jesper Harder wrote:
>
>> tkoelman@xs4all.nl (Tom Koelman) writes:
>>
>>> On inspection of the reply I noticed that it didn't have its
>>> References header set, but did have a header called In-Reply_To:
>>> with the correct message-id.
>>>
>>> Is there some way to make gnus use this information?
>>
>> Hmm, I would have thought Gnus already does it.
>
> You are right, thanks. 
> I had set gnus-summary-thread-gathering-function to
> gnus-gather-threads-by-references. When I turned that off the thread
> was gathered nicely. 

Hmm, I think this patch should make work with
gnus-gather-threads-by-references, too: