Non-standard escape sequences from Crystal Reports

When our customer runs Crystal Reports reports created in an old version
of CR and edited with CR XI, he gets a large number of warnings in his
Postgres log files that look like this:

2010-10-05 11:28:00 EDTWARNING: nonstandard use of \\ in a string
literal at character 159
2010-10-05 11:28:00 EDTHINT: Use the escape string syntax for
backslashes, e.g., E'\\'.

I just ran a test in which I connected to a different database server
for which my log settings showed the statements that generated warnings.
The statement was this:

2010-10-05 11:28:00 EDTSTATEMENT: select relname, nspname, relkind from
pg_catalog.pg_class c, pg_catalog.pg_namespace n where relkind in ('r',
'v') and nspname like 'public' and relname like 'coil\\_status' and
nspname not in ('pg_catalog', 'information_schema', 'pg_toast',
'pg_temp_1') and n.oid = relnamespace order by nspname, relname

Coil_status is the name of one of the two relations used in the report.

Apparently, at some time in the distant past, it was necessary to do
something special for underscore characters. The two backslashes are
apparently being ignored, because the report operates correctly.

I tried running the same report on my computer, I did not get any
warnings. Our customer and my computer are both running Postgres 8.4.
I tried copying the customer's postgres.conf file onto my system and
restarting my Postgres service, and I still got no warnings.

Can anyone tell me if there is some setting that will stop these
warnings from showing up (other than turning off warning messages
completely, which I am about to suggest that the customer do)? Also,
does anyone know why my computer is not showing warnings while our
customer's system is?

Thanks very much!

RobR