jQuery HTML5 placeholder fix Written in CoffeeScript and converted into JavaScript later This is supposed to deal with dynamically loaded elements Not tested though

placeholder.js

/**
 * This hack creates the placeholder effect on old browsers
 *
 * Source: http://www.hagenburger.net/BLOG/HTML5-Input-Placeholder-Fix-With-jQuery.html
 * Dependency: jQuery & Modernizr
 *
 * It also add a class to the input so you can style it to look like normal placeholder
*/

jQuery(function($) {
  var placeholder_class, placeholder_selector;
  if (!Modernizr.input.placeholder) {
    placeholder_class = 'browser-hack-placeholder';
    placeholder_selector = '[placeholder]';
    $(document).on('focus', placeholder_selector(function() {
      var input;
      input = $(this);
      if (input.val() === input.attr("placeholder")) {
        input.val("");
        input.removeClass(placeholder_class);
      }
    }));
    $(document).on('blur', placeholder_selector, function() {
      var input;
      input = $(this);
      if (input.val() === "" || input.val() === input.attr("placeholder")) {
        input.addClass(placeholder_class);
        input.val(input.attr("placeholder"));
      }
    });
    $(document).on('submit', 'form', function() {
      $(this).find("[placeholder]").each(function() {
        var input;
        input = $(this);
        if (input.val() === input.attr("placeholder")) {
          input.val("");
        }
      });
    });
    $(placeholder_selector).trigger('blur');
    $(document).ajaxSuccess(function() {
      $(placeholder_selector).trigger('blur');
    });
  }
});

placeholder.js.coffee

###*
 * This hack creates the placeholder effect on old browsers
 *
 * Source: http://www.hagenburger.net/BLOG/HTML5-Input-Placeholder-Fix-With-jQuery.html
 * Dependency: jQuery & Modernizr
 *
 * It also add a class to the input so you can style it to look like normal placeholder
###

jQuery ($) ->
  unless Modernizr.input.placeholder
    placeholder_class = 'browser-hack-placeholder'
    placeholder_selector = '[placeholder]'

    $(document).on 'focus', placeholder_selector ->
      input = $(this)
      if input.val() is input.attr("placeholder")
        input.val ""
        input.removeClass placeholder_class

    $(document).on 'blur', placeholder_selector, ->
      input = $(this)
      if input.val() is "" or input.val() is input.attr("placeholder")
        input.addClass placeholder_class
        input.val input.attr("placeholder")

    $(document).on 'submit', 'form', ->
      $(this).find("[placeholder]").each ->
        input = $(this)
        input.val ""  if input.val() is input.attr("placeholder")

    # Display placeholders on page load
    $(placeholder_selector).trigger('blur')
    # Display placeholders after ajax event
    $(document).ajaxSuccess ->
      $(placeholder_selector).trigger('blur')