In trying to use DHTML scriptlets with Internet Explorer (v6 on
Windows 2000 Professional), I have created a richtext edit control for
managing content in a web site.  The scriptlet is written in ASP and
HTML and is contained on another ASP page.

I have been able to successfully pass large amounts of data from the
scriptlet to the container without a hitch.  After some javascript
calls that set the value of a hidden text input or textarea (I have
tried both), I then call a method to submit the form.  The container
page holds the form which submits to itself.

When the javascript calls the form submit method, I am getting an
"Invalid Syntax" but only if the data is larger than 1750 characters
or so (this might indicate a limit of 2048 when taking into account
other variables that are being passed).  It also seems similar to the
limitation for URLs in Internet Explorer:

http://support.microsoft.com/default.aspx?scid=KB;EN-US;Q208427&

I have tried numerous ways of trying to solve this problem and I find
little help from my Google searches.  I hope this is a simple problem
that someone has encountered before.

The microsoft knowledge base article says that POST has no
limitations.
Try and change the form submit type method from GET to POST.
Change the code in the ASP used to generate the form to:

<form method="post" action="whaterver your action is">
:
:
</form>

If you checkout how hotmail handles submissions (or even
answers.google.com); it uses the POST method for the message body
(which can be > 2k).

Once you change your form, your ASP code will also need to be changed.
In particular: the way it accesses the variables submitted on the web
page. You will need to replace all occurances of:

Request.QueryString("your-variable-name") 

to:

Request.Form("your-variable-name") 

For more information on how to differences between accessing data from
GET adn POST in ASP check out the site:
http://www.dit.gov.bt/~takeshi/material/web/asp/contents3.html

Hope this helps.