How to Trace IP address using java script?

<script language="JavaScript">
    VIH_BackColor = "palegreen";
    VIH_ForeColor = "navy";
    VIH_FontPix = "16";
    VIH_DisplayFormat = "You are visiting from:<br>IP Address: %%IP%%<br>Host: %%HOST%%";
    VIH_DisplayOnPage = "yes";
</script>
<script language="JavaScript" src="http://scripts.hashemian.com/js/visitorIPHOST.js.php"></script>