How can i put popup box captcha on managed file remove button?
I have solved it. I have hide remove button access. and then put my own remove button, and open dialog box in form to display popup box. 



please see code. 

drupal_add_library('system', 'ui.dialog');
drupal_add_js('jQuery(document).ready(function(){
    jQuery("#clicky").live("click", function(){
        jQuery("#dialog").dialog({ modal: true ,height: 250,width: 350, buttons: [
            {
            text: "Cancel",
            click: function() {
                jQuery(this).dialog("close");
            }},
            {
                text: "Submit",
                click: function() {  
                     jQuery("#dialog-form").submit();
            }}
        ]});});});', 'inline');