form uploading prob

[cfemocha]

Im trying to write the below code using javascript
[code]
<form method="post" enctype="multipart/form-data" action="test.php">
<input type="File" name="filename" id="filename">
<input type="Submit" name="action2" value="Submit">
</form>
[/code]

Below is a snipet of my javascript
[code]
var oHiddenForm = oIFrame.document.forms[0];
for (var i=0 ; i < oForm.elements.length; i++)
{  --- code ---
    oHidden.value = oForm.elements[i].value;
    oHiddenForm.appendChild(oHidden);
}
oHiddenForm.encoding = "multipart/form-data";
oHiddenForm.action = oForm.action;
oHiddenForm.submit();
[/code]

all other form input values seemed to work fine, except the file that im uploading.
Im guessing [b]oHiddenForm.encoding = "multipart/form-data";[/b]  is causing the prob, I've tried everything and
still can't figure it out.
Please help!

[fenway]

Is this a browser-specific issue? Have you checked to see what the browser actually produces?