jquery - nested css style on li element on hover

I have my markup something like this.

  

    
Buy
    
Sell
    
Community
    
Languages
    
My Account
  

Now I have put jQuery to add a class inside a class selected. So when user hover on alink(here on Buy link) the markup becomes like this

  

    
Buy
    
Sell
    
Community
    
Languages
    
My Account
  

Now I want to give style only the li whose a class is selected.
My style for the li is to just give border to the li element. So can someone tell me how to do this? Any help and suggestions will be really appreciable. Thanks....

Update
I want to give border to my li element not the a so please help me in that field.Can this be achieved in simple css? Hey I am still for the answer...