title: Sorting on multiple column header in liferay searchcontainer
body: <p>i done with sorting on single column header of liferay searchcontainer in liferay 6.0.6.
  now i want to apply sorting on multiple fields i.e FirstName,LastName,Date either in asc or desc order.
  can anybody help me out..</p>
  
  <p>Thanks in advance....</p>