There are still a handful of places where a statement is created but no stmtid is assigned. Can you check those?
src/pl/plpgsql/src/pl_exec.c:2815 src/pl/plpgsql/src/pl_exec.c:4580 src/pl/plpgsql/src/pl_gram.y:907 -- Peter Eisentraut http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services