Notifying members in a separate thread of execution

[The One]

I run SMF on a Windows 2k server  and it uses SMTP for email notification to members.
The problem is on some board I have around 80 members who want to be notified on new topics, in this board whenever a new topic is posted after I click submit the page sort of hangs, I think this is because of the processing of the email sending.
Is there any way this coul be put in some other process/thread so that the poster does not see this "hung" page happen?

[The One]

Does PHP allow spawning threads?

[[Unknown]]

Not really.  There's PCNTL, but that's only for CGI/CLI and off on 99% of servers anyway.

The best you can do is put it in a "todo list" and do it later, but there are problems with that, including race conditions, as well.

-[Unknown]

[The One]

Hmmm... ok  .
Is there anything I can do on the web server to improve this?

[[Unknown]]

It's been impressed upon me that qmail is a lot more efficient in the respect of sending emails than exim, but I haven't any experience there I'm afraid - nor any idea how to switch.

-[Unknown]

[The One]

I have a new Debian machine now where I was going to install some mail daemon? I was wondering which one to use qmail/cmail/fetchmail/sendmail etc..
I am thinking of going in for qmail as "Unknown" had suggested, but just wanted to ask around if there was something better.