function getIEVersion(){
    var agent = navigator.userAgent;
    var reg = /MSIE\s?(\d+)(?:\.(\d+))?/i;
    var matches = agent.match(reg);
    if (matches != null) {
        return { major: matches[1], minor: matches[2] };
    }
    return { major: "-1", minor: "-1" };
}

function IncludeJavaScript(jsFile)
{
  document.write('<script type="text/javascript" src="'
    + jsFile + '"></scr' + 'ipt>'); 
}

var ie_version =  getIEVersion();
var is_ie_gt_9 = ie_version.major > 9;

//alert("IE version is "+ie_version.major);

if (is_ie_gt_9) {
//  alert("loading 1.7.1");
  IncludeJavaScript('/javascripts/prototype-1.7.1.js');
} else {
//  alert("loading 1.7");
  IncludeJavaScript('/javascripts/prototype-1.7.js');
}