IE Placeholder JavaScript replacement

ieplaceholder.js

if (!Modernizr.input.placeholder) {

    // always declare javascript variables at the top of the script
    var $elements, $i, $x, $len, $formInput, $inputField, $form;

    $form = document.getElementById('contact-us').elements;

    $i = 0;

    //set placeholder values for internet explorer
    for ($len = $form.length; $i < $len; $i += 1) {

        if ($form[$i].getAttribute("placeholder") != undefined) {

            $form[$i].value = $form[$i].getAttribute("placeholder");

        } // if not undefined
    } // end for loop

    $inputField = document.forms.contactUs.getElementsByTagName('input');

    $x = 0;

    // loop through input areas to make sure placeholder disappears on focus
    for ($len = $inputField.length; $x < $len; $x += 1) {

        // Don't change the submit input!
        if ($inputField[$x].type !== "submit") {

            // Give placeholder text a grey colour
            $inputField[$x].style.color = "#999";

            //Delete the placeholder text and change CSS text colour to black on user focus
            $inputField[$x].onfocus = function () {

                this.value = "";
                this.style.color = "#000";

            };

        }

    } // if not undefined
} // end modernizr