I had the same problem, but I found that you have to use the ID value of the textarea, not the NAME. Try this:
<textarea rows="10" ID="strRBody" cols="64"></textarea>
You can give it whatever name you want, but you have to define the ID attribute and use that as the value for strTextAreaName.
HOWEVER, the strFormName does use the NAME attribute on the <FORM> tag.
It can be confusing...one uses ID, the other uses NAME.

Once I got it straight, it worked fine for me in IE and Firefox.
Thanks,
William Eaton, MCSE
iTech Computer Solutions, LLC