function sleep(seconds) {
    var start = new Date().getTime();
    while (new Date() < start + seconds*1000) {}
    return 0;
}


function setHomepage_portal(pageURL)   
{
	if (document.all)   
    {   
		document.body.style.behavior='url(#default#homepage)';   
		document.body.setHomePage(pageURL);   
    }   
    else if (window.sidebar)   
    {   
		if(window.netscape)   
		{   
			try  
			{     
				netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");     
			}     
			catch (e)     
			{     
				alert( "浏览器拒绝此操作，请在地址栏内输入 about:config 然后将 signed.applets.codebase_principal_support 设为true" );     
			}   
		}    
		var prefs = Components.classes['@mozilla.org/preferences-service;1'].getService(Components. interfaces.nsIPrefBranch);   
		prefs.setCharPref('browser.startup.homepage',pageURL);   
	}   
}