function goInstall(appname, appregname, version, url) {
	var proceed = true;

	// trigger the install
	if(proceed) {
		if (InstallTrigger.enabled()) {
			if(checkVersion(appname, appregname, version)) {		
				var xpi = new Object();
				xpi[appname] = url;
				InstallTrigger.install(xpi);
			}
		} else {
	        	window.alert("Software installation has been disabled in your browser.");
		}
	}	
}

function checkVersion(appname, appregname, version) {
	return InstallTrigger.compareVersion(appregname, version) ||
			confirm("It seems you have just installed the same " + appname + " version.\nContinue anyway?");
}