Getting value of bind variables

Hell l,
I am trying to debug a query that gives an error. The error in the
application server log is
" ERROR: operator does not exist: timestamp without time zone = character
varying
Hint: No operator matches the given name and argument type(s). You might
need to add explicit type casts.
Position: 1274"
How can I get the value of the $1,$2 etc in the query?
WHERE MST.CMPCOD= $1
AND UPPER ( CUSINDINF.FAMNAM )= UPPER ($2)
AND UPPER ( CUSINDINF.INITLS )= UPPER ($3)
AND ( CUSINDINF.MEMDOB ) = ($4)
AND MST.CUSNUM <> $5

It looks like the error is for the condition ( CUSINDINF.MEMDOB ) = ($4) ,
memdob being a date of birth (timestamp) column. When I try the query at
psql with some values, the data is retrieved OK. Is there some logging
available in PostgreSQL that will tell me what values were actually used?
As of now, I am trying with logging level set to debug5 in postgresql.conf
for all logging options. But what is the 'correct' approach?

Regards,
Jayadevan

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