proftpd and sshd delays

[James Duff <dingopuppy@gmail.com>]

Hi, this is my first attempt at posting to one of these mailing lists,
so please forgive me if I have not included enough information or if
this has already been covered (I've looked!).

I'm running a server at a school for the purpose of providing internal
apache http access, and have come across a couple of problems.

Both sshd, and proftpd are very slow to respond. I've noticed this in
sshd under debian on previous versions and machines also. Sshd asks
for a username almost immediately when I connect, but there is a
substantial time before it asks for a password.

Proftpd also has a significant delay before responding to login information.

I'm not sure where to look for logs regarding these events, as nothing
relevant seems to be in /var/log/auth.log.

Is this a common problem? I'm using default configurations where
possible, and have not changed anything regarding authentication.

Is there a likely problem in getting passwords on my machine?

If you can suggest either a solution, or somewhere I can begin to find
out whats wrong, please let me know.

Thanks,
James