use this JS in all pages
and remove your current thing on the header this one is using JS only..

Code:

document.write('<div id="loading_wrapper" style="display:none;"></div><style>#loading_wrapper{background: #95C715 url(http://nathanadhitya.webs.com/forumflses/ajax_loading.gif) 50% 40% no-repeat; border:1px solid #7BA60D;color:#fff;text-align:center;padding:5px 0 8px;width:8%;height: 2%;top:0%;left:46%;-moz-border-radius:0 0 5px 5px;-webkit-border-bottom-right-radius:5px;-webkit-border-bottom-left-radius:5px;border-radius:0 0 5px 5px;position:fixed;-moz-box-shadow:0px 3px 5px rgba(0,0,0,0.2),inset 0px -1px 0px rgba(255,255,255,0.2);-webkit-box-shadow:0px 3px 5px rgba(0,0,0,0.2),inset 0px -1px 0px rgba(255,255,255,0.2);box-shadow:0px 3px 5px rgba(0,0,0,0.2),inset 0px -1px 0px rgba(255,255,255,0.2);}</style>');
$("#loading_wrapper").fadeIn(1500);
window.onload=function(){$("#loading_wrapper").fadeOut(1500);};

anyways i would just suggest to use my idea.... LOL
anyways i changed the default IPB link... with my own stupid webs site...
here's the image from IPB Script

Code:

document.write('<div id="loading_wrapper" style="display:none;"></div><style>#loading_wrapper{background: #95C715 url(http://community.invisionpower.com/filestore/public/style_images/master/ajax_loading.gif) 50% 40% no-repeat; border:1px solid #7BA60D;color:#fff;text-align:center;padding:5px 0 8px;width:8%;height: 2%;top:0%;left:46%;-moz-border-radius:0 0 5px 5px;-webkit-border-bottom-right-radius:5px;-webkit-border-bottom-left-radius:5px;border-radius:0 0 5px 5px;position:fixed;-moz-box-shadow:0px 3px 5px rgba(0,0,0,0.2),inset 0px -1px 0px rgba(255,255,255,0.2);-webkit-box-shadow:0px 3px 5px rgba(0,0,0,0.2),inset 0px -1px 0px rgba(255,255,255,0.2);box-shadow:0px 3px 5px rgba(0,0,0,0.2),inset 0px -1px 0px rgba(255,255,255,0.2);}</style>');
$("#loading_wrapper").fadeIn(1500);
window.onload=function(){$("#loading_wrapper").fadeOut(1500);};