I doublechecked, and mobile IE does indeed support Javascript (I could have sworn it did, but I wanted to doublecheck).
As for why the button isn't working.. I just re-read your other post, and noticed you said that the submit on the replies are coded the same way. Obviously, those work well because (with the exception of this post I'm making now) all other posts in this topic and for the past month or so were completely and totally on my Dash.
That makes it particularly puzzling as to why it works here, but not there.
I mean no disrespect, but is there a semi-colon or some other very very minor typo somewhere that the "big browsers" are overlooking that is causing the mobile browser to snag when processing the function call? Is there anything else, however trivial it may seem to you, that is different between the implementation of the replies-submit and the implementation on the login of the beta that may be causing it? maybe a hard-coded URL reference somewhere or even where the handler appears in relation to other html tags? (just trying to think of possible errors that I myself have made in my web authoring past that took days to find what I did wrong)
Actually, I think I may have found it. I don't know enough about how your site is coded to know if this is going to be changeable. As I was writing this reply, I took another look at the code from this page (which works) and the beta page (which doesn't work), and pasted them into a text document side-by-side to compare, and have the following observation (edited for brevity and comparison purposes, working code first):
--------------------
function __doPostBack(eventTarget, eventArgument) {
var theform;
[if statement to handle a condition that could be different based on the browser]
[stuff to actually handle the request]
}
--------------------
var theForm = document.forms['aspnetForm'];
[if statement to handle a condition that could be different based on the browser]
function __doPostBack(eventTarget, eventArgument) {
[stuff to actually handle the request]
}
--------------------
Items of note is that within the first (working) example, the variable declaration is within the function definition. The second, although it's still within a javascript tag, it's not explicitly defined within the definition. Instead, it is defined (along with error catching based on browser version to make the rest work) outside of the function. So, my thinking now is that either the variable definition and/or error catching if statement is not being processed when the rest of the function is called (using a mouse click), which is causing it to basically stare at me when I click, instead of submitting the form. Would it be possible to encapsulate those definitions inside the function, or is it not possible based on the rest of your programming?
This could be an issue because of the relatively limited memory of mobile devices and mobile IE trying to conserve memory (almost like in the old days of DOS 
)
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