How to customize tinyMCE built-in buttons like -silverstripe- CMS

when I had a look on http://demo.silverstripe.com/admin/ [user-name:admin ,password:admin]

I noticed that they have overridden the insert image button and also the insert flash button

The Question is What is the easiest way achieve this or the best guide ?

note : I'm not using sliverstripe or any ready made开发者_StackOverflow CMS

Adding your own buttons is quite well described at the TinyMCE web: http://tinymce.moxiecode.com/tryit/custom_toolbar_button.php

Pasted from site:

tinyMCE.init({
    mode : "textareas",
    theme : "advanced",
    theme_advanced_buttons1 : "mybutton,bold,italic,underline,separator,strikethrough,justifyleft,justifycenter,justifyright, justifyfull,bullist,numlist,undo,redo,link,unlink",
    theme_advanced_buttons2 : "",
    theme_advanced_buttons3 : "",
    theme_advanced_toolbar_location : "top",
    theme_advanced_toolbar_align : "left",
    theme_advanced_statusbar_location : "bottom",
    plugins : 'inlinepopups',
    setup : function(ed) {
        // Add a custom button
        ed.addButton('mybutton', {
            title : 'My button',
            image : 'img/example.gif',
            onclick : function() {
                // Add you own code to execute something on click
                ed.focus();
                ed.selection.setContent('Hello world!');
            }
        });
    }
});

Just change this as you please.