Bypass Client Side Validation when using Ajax.BeginForm

Question

When using Html.BeginForm("SaveAction") and Html.EnableClientValidation() you can bypass client side validation using

<script type="text/javascript">
    document.getElementById("mySaveButtonId").disableValidation = true;
</script>

Does anyone know how to achieve similar results with

Ajax.BeginForm("SaveAction", new AjaxOptions())

Reasoning: I need to enable saving in-valid form data, which auto saves itself every minute or so.