function activate_children( id )
{
    // attach the appropriate onclick function to '<id>-link'
    // swap out the button image attached to '<id>-button-image'

    $( id + '-button-image' ).className = 'button-additional-information' ;

    $( id + '-link' ).onclick = 
        (function( theid )
         { return function()
           { 
               Effect.toggle( $( theid + '-child-product-box' ) , 'blind' , { duration : 0.38 } ) ;
               
               return false ;
           }
         })( id ) ;

    $( id + '-image' ).className = 'button-additional-information-image' ;
    
    return ;
}