BUG #5270: escape warning even with standard behavior

The following bug has been logged online:

Bug reference: 5270
Logged by: Lothar
Email address: lotharbongartz(at)hotmail(dot)com
PostgreSQL version: 8.4
Operating system: Windows XP Professioanl
Description: escape warning even with standard behavior
Details:

I am migrating from a hug SQL Server project.
I have to import a 4G database.

To switch off the escape character behavior, I changed the entry in
postgresql.conf to
#standard_conforming_strings = on

Despite of this, I get following warnings when importing data:
State=22P06, Err=-1, Msg=WARNING: nonstandard use of escape in a string
literal

According to the documentation I should not get this warning.

Do I have to use another measurement additionally to the postgresql.conf
change, if I do not like characters to be treated as escape characters?

The warnings are by nature always related with error return codes for the
sql commands and therefore are destroying the intended program flow.