PHP or MSIE Problem?

All, When I submit a form from MSIE, under certain circumstances some of the fields don't make it into the $_POST array. I am building a CMS that accepts images and text entered into an HTML form. If I submit a form from MSIE, and if the text contains special characters (like T [TM] for example), some of the $_POST fields are not populated in PHP. This problem does not occur on Mozilla or Safari. The php version is 4.3.4, and is running on Linux. The MSIE version is 6.0.2800.1106.xpsp2.030422-1633. Here's a demonstration of the problem: http://hartshorne.ca/sandbox.php Can anyone tell me if this is a common problem? Is this a purely MSIE bug, or could PHP be a factor? Thanks!! Beau