I've just checked my log book, and the only thing signed off is a generic entry from the CFI stating that all logbook entries were correct (OK, there are a few other things, but nothing about doing X-country apart by QXC). I did, however, keep a separate record in one of the columns of all the time I spent doing X-country flying. This was just whenever I left the circuit, not necessarily landing away.
The CAA issued my PPL without comment (in 2002). Is this something more recent?