Celius Clefia wrote:
> So if a problem on netbsd-help was solve between 2 people in private,
> the  public cannot view the conversation that took place.

Correct.  

> Threads are sorted automatically according to subject formating.

Approximately.  Email servers assign a message id to each message, and
most clients, when responding to a message, indicate the id of the message
it's replying to.  This information appears in the message's headers.  Any
system (including your own client) that looks at a message archive can
read the message headers and organize them by thread if it so chooses.  

For instance, you message -- the one I'm answering -- has Message-Id 
200706290139.l5T1dAfv016262@sdf.lonestar.org.  It is in reply to 
D00105B2-2E05-4CAD-BF70-63B1A16078C2@mac.com.  My email client will insert
an In-Reply-To header with your message's ID in it.  And so on, until we
get tired of talking to each other.  

Your email client probably has a way to display this message's headers. 
You'll find some of what I'm describing there.  

HTH.  

--jkl