IE8 crashes when styling input[type=submit] with CSS3 PIE
===

Sometimes the page works and you need to refresh the page to see it crash.

You can see a live sample here: http://rcnhca.org.uk/sites/first_steps/account/ (ie7 works fine, I am not supporting ie6)

I am attempting to style my submit button with the following values:

    a.button, input.button {
        border: 2px solid #3A90A7;
        border-radius: 5px 5px 5px 5px;
        color: #202D32;
        display: block;
        float: left;
        height: 2.6em;
        line-height: 2.6em;
        margin: 0.667em 0.333em;
        padding: 0 1em;
        position: relative;
        text-decoration: none;
    }

    a.button:hover, input.button:hover{
    	border: #202d32 solid 2px;
    	box-shadow: 0 1px 2px rgba(0, 0, 0, 0.25), 0 0 3px #FFFFFF inset;
    	-moz-box-shadow: 0 1px 2px rgba(0, 0, 0, 0.25), 0 0 3px #FFFFFF inset;
    }
    
    input[type=submit] {
    	behavior: url(http://rcnhca.org.uk/sites/first_steps/PIE.htc);
    	position: relative;
    	-pie-poll:true;
    }
    
    a.button:hover, input.button:hover{
    	-pie-box-shadow: none;
    }
    
    .button {
    	-pie-background: linear-gradient(top, #ffffff 0%,#e5e5e5 100%);
    }
    
    .button.active {
    	-pie-background: linear-gradient(top, #b7b7b7 0%,#b7b7b7 8%,#e5e5e5 8%,#ffffff 100%);
    }

Finally, the submit button in all it's glory:

    <input id="submitbtn" class="button omega" type="submit" value="Create your account" name="submit">

Does anyone know what could be causing this crash? I don't get any information apart from a script is causing the page to run slowly.
