Need query parameter in logs

    I am trying to help debug a application that is deployed in the
field. I suspect that it is sending some unexpected values to some
stored procs, but the logs look very much like:

Feb 9 14:29:26 localhost postgres[3138]: [122-1] LOG: statement:
Select * from game_state_set_disqualified( $1, $2, $3, $4 )

    How can I find out what $1, $2, $3, $4 are short of recompiling the C
++ client code?

Thanks
Robert Perry