<STYLE type="text/css">
<!--
BODY {
scrollbar-face-color: 000000;
scrollbar-highlight-color: 00ff00;
scrollbar-3dlight-color: 000000;
scrollbar-darkshadow-color: 000000;
scrollbar-shadow-color: 00ff00;
scrollbar-arrow-color: 00ff00;
scrollbar-track-color: 000000;
}
-->
</STYLE>



PS: ponha isso em qualquer lugar entre as tags <body> e </body>