function externalLinks() { 
 if (!document.getElementsByTagName) return; 
 var anchors = document.getElementsByTagName("a"); 
 for (var i=0; i<anchors.length; i++) { 
   var anchor = anchors[i]; 
   if (anchor.getAttribute("href") && 
       anchor.getAttribute("rel") == "external") 
     anchor.target = "_blank"; 
 } 
} 
window.onload = externalLinks;

function jah(url,target) {
    // native XMLHttpRequest object
    document.getElementById(target).innerHTML = 'strpení, data se načítají...';
    if (window.XMLHttpRequest) {
        req = new XMLHttpRequest();
        req.onreadystatechange = function() {jahDone(target);};
        req.open("GET", url, true);
        req.send(null);
    // IE/Windows ActiveX version
    } else if (window.ActiveXObject) {
        req = new ActiveXObject("Microsoft.XMLHTTP");
        if (req) {
            req.onreadystatechange = function() {jahDone(target);};
            req.open("GET", url, true);
            req.send();
        }
    }
}    

function jahDone(target) {
    // only if req is "loaded"
    if (req.readyState == 4) {
        // only if "OK"
        if (req.status == 200) {
            results = req.responseText;
            document.getElementById(target).innerHTML = results;
        } else {
            document.getElementById(target).innerHTML="jah error:\n" +
                req.statusText;
        }
    }
}