[Octane]

<form action="http://jquery.com">
    <fieldset>
        <input type="text" value="Press Enter">
        <input type="submit" value="Submit">
    </fieldset>
</form>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script>
$(function () {

    $("input:text").keydown(function (event) {
        if (event.keyCode == 13) {
            event.preventDefault();
        }
    });

});
</script>

http://javascript.ru/tutorial/events...po-umolchaniyu