/**
  * sets the new image url
  *
	* @param object img the img tag
	* @param string s_prefix prefix for the image name
	* @param string s_postfix postfix for the image name
	* @return void
  */
	function img_new_src(img, s_prefix, s_postfix) {
		// determine basename
		s_filename 		= img.src;
		n_slash				= s_filename.lastIndexOf('/') + 1;
		n_underscore	= s_filename.lastIndexOf('_');
		n_dot					= s_filename.lastIndexOf('.');
		s_extension		= s_filename.substring(n_dot);
		s_basename 		= s_filename.substring(n_slash + s_prefix.length, n_underscore);

		// determine article and group
		n_underscore		= s_basename.indexOf('_');
//		s_this_group		= s_basename.substring(0, n_underscore);
//		s_this_article	= s_basename.substring(n_underscore + 1);
		
		// change the image src if allowed
//		if (s_group != s_this_group || s_article != s_this_article) {
			img.src = s_rooturl + s_gfxdir + '/' + s_prefix + s_basename + s_postfix + s_extension;
//		} // end: if
	} // end: function img_new_src()
  
  
  
  /**
  * creates a popup link to a detail picture of a given thumbnail
  *
	* @param string s_thumb the URL of the thumbnail
	* @return void
  */
  function thumb(s_thumb) {
    var s_popup_url = s_rooturl + 'index.php/intern/popups/image.html';
    var s_url_param = 'show=' + s_thumb;
    var s_win_param = 'width=150,height=150,scrollbars=yes,resizable=1,menubar=no';
    
    thumb_popup = window.open(s_popup_url + '?' + s_url_param, 'thumb_popup', s_win_param);
    thumb_popup.focus();
  } // end: function thumb()