I wrote:

> Simon Josefsson writes:
>
>> I think it might be easier to have nnir never re-use article numbers.
>> But I'm not familiar enough with nnir to fix this.
>
> I'm afraid this would break solid groups, which work ok for engines
> that support ordering of returned articles by delivery-date or
> something comparable instead of "Score".

Actually, the same trick that nnweb uses to avoid caching anomalies
with ephemeral groups could be applied to nnir as well.  nnweb uses
message-unique-id to generate names for ephemeral groups, and pushing
such an id into nnir's query parameters has the same effect.

Tassilo: Could you try to reproduce the problem with the attached
patch?  If the problem is actually caching related, the symptoms
should disappear.

regards,
andreas