Well, for me at least.
When I search for new posts, I get this debug dump
SQL Error : 1062 Duplicate entry '1844444536' for key 1
INSERT INTO phpbb_search_results (search_id, session_id, search_time, search_array) VALUES(1844444536, 'c925605d34ffc48c076294426a444d1c', 1151332076...