Placeholder fallback with jQuery

placeholder.js

/**
* Fallback for "Placeholder" attribute in old browsers
* source: http://www.scriptiny.com/2012/08/html5-placeholder-fallback-using-jquery/?utm_source=html5weekly&utm_medium=email
*/

$(document).ready(function() {
 
    if (!('placeholder' in document.createElement('input'))) {
        $('input[placeholder]').each(function() {
            var val = $(this).attr('placeholder');
            if ( this.value == '' ) {
                this.value = val;
            }
            $(this).focus(function() {
                if ( this.value == val ) {
                    this.value = '';
                }
            }).blur(function() {
                if ( $.trim(this.value) == '' ) {
                    this.value = val;
                }
            })
        });
 
        // Clear default placeholder values on form submit
        $('form').submit(function() {
            $(this).find('input[placeholder]').each(function() {
                if ( this.value == $(this).attr('placeholder') ) {
                    this.value = '';
                }
            });
        });
    }
});