Log actual params for prepared queries: TO-DO item?

We'd like to attempt some log replay to simulate real loads, but
in 8.1.2, it appears the formal parameters are logged ('$')
instead of the actuals for prepared queries, e.g.:

EXECUTE <unnamed>  [PREPARE:  UPDATE sessions SET a_session = $1
WHERE id = $2]

Thoughts on making this a to-do item?

Ed