How to confirm that mailform has in fact sent a message?

I have a working Flash mailform that is pointing to Comcast’s form created when a generic website is built. When that generic form is used in html format a confirmation page pops up with a standard “Thank You, etc.”. I have a Flash thank you page built as well but it has nothing to do with what is going on on the server since I don’t know how to connect these two. So in case there is an error on the server’s side Flash will not detect it and the user will think his e-mail went through. Is there a way of writing a code that would take care or of it? The html address of the form that I’m addressing with Flash and the “Thank You” page is the same - just the contest changes. And here’s the source for the latter (not much to it but what is VLINK or LINK - they seem to be the only unique things in this code?):
<!DOCTYPE HTML PUBLIC “-//W3C//DTD HTML 3.2 Final//EN”>
<!-- Generated by Oracle’s Dynamic HTML Generation Package -->
<HTML>
<HEAD><script>function <TITLE>Mailform Entry Submitted</TITLE>
</HEAD>
<BODY BGCOLOR=#ffffff FGCOLOR=#000000 TEXT=#000000 VLINK=#6495ed LINK=#0000cd>
<H1>Thank You For Submitting Mailform!</H1>Thank you, visitor13, for submitting an entry.<BR>
<HR><TABLE WIDTH=‘100%’><TR><TD align=center><A HREF=“http://home.comcast.net/”><img src="/global-images/guestbook/back.jpg" ALT=‘Go Back’ border=0></a></TD><TD align=center><A HREF=“http://home.comcast.net/~tenant13”><img src="/global-images/guestbook/home.jpg" ALT=‘Go To My Home Page’ border=0></a></TD></TR></TABLE>

</BODY>
HTML>