var arydomain = new Array(".com.cn",".net.cn",".org.cn",".gov.cn",".com",".cn",".net",".cc",".org",".info",".biz",".tv"); 
var domain = document.domain;
var tmpdomain = ""; 

for(var i=0;i<arydomain.length; i++) 
{ 
tmpdomain = arydomain[i]; 
if(domain.indexOf(tmpdomain) != -1) 
{ 
domain = domain.replace(tmpdomain,""); 
domain = domain.substring(domain.lastIndexOf(".")+1,domain.length); 

domain = domain + tmpdomain; 

break; 
} 

}