HTML <form> Value Does Not Get Posted

Basically, everything is written in ASP. Firstly, a user fills in an
online (ASP) form, and then submits it to another ASP page (e.g.
Send.asp). Now Send.asp retrieves all the form data and sends another
HTML form via an e-mail. I then receive and open the HTML email(s). Now
everything is going fine up until this point.

When I hit the submit button from the e-mail, it posts all the form
data to another ASP page.

Now this is when things start to get a little weird.

Half the time when I submit the form via Outlook 2003 message, the
other ASP page would load will all the form data intact. Every other
time, the other ASP page would load will NO form data at all; just
blank text boxes, textarea, checkboxes, etc ...

I've done a few experiment of my own in the hope of finding some
answer. So far, I've only seen this happen to Outlook 2003 and not 2000
(we have a mixed between those 2 versions).

Also, it only happens to users in the same state as where the IIS
server is located. For example, the server is located in state A, so
any users with Outlook 2003 in State A will experience this problem
half the time. Other users in State B, C, D, etc ... using Outlook 2003
does not experienc this problem. Because the link is a lot slower for
our interstate users, I'm starting to think that maybe network speed
has a part in this behaviour.