A shim for older versions of jQuery which don't have the `on` method defined.

gistfile1.js

(function( $ ) {
  'use strict';

  if ( !$.fn.on && $.fn.live && $.fn.bind ) {

    $.fn.on = function() {

      var args = createObjectFromArgs( arguments );

      if ( args.selector ) {
        this.find( args.selector ).live( args.events, args.data, args.handler );
      } else {
        this.bind( args.events, args.data, args.handler );
      }

      // support chaining
      return this;
    };

  }

  function createObjectFromArgs( args ) {

    var o = {},
      argumentNames = getArrayOfArgumentNames( args );

    $.each( argumentNames, function( index, argumentName ) {
      o[ argumentName ] = args[ index ];
    } );

    return o;

  }

  function getArrayOfArgumentNames( args ) {

    if ( args.length === 2 ) {
      return [ 'events', 'handler' ];
    }

    if ( args.length === 3 && typeof args[ 1 ] === 'string' ) {
      return [ 'events', 'selector', 'handler' ];
    }

    if ( args.length === 3 && typeof args[ 1 ] !== 'string' ) {
      return [ 'events', 'data', 'handler' ];
    }

    if ( args.length === 4 ) {
      return [ 'events', 'selector', 'data', 'handler' ];
    }

    throw new Error( 'could not determine the order of arguments to jQuery.fn.on' );

  }

}( jQuery ));​

Reinventing the wheel :(

https://github.com/MoonScript/jquery-on-off-shim/blob/master/jquery.on.off.js