log_destination = csvlog, line breaks interfere in analysis

Dear all,

I've started collecting log information in CSV format, but I need a way
to customize it.
Problem is that I'm collecting slow statements, and the statements have
\n (newline) character, and the piece of

2012-09-17 14:25:33.150
BRT,"thedb","thedb",15660,"10.10.20.1:33485",5054d3ab.3d2c,1,"SELECT",2012-09-15
16:14:51 BRT,10/204822,0,LOG,00000,"duração: 505.494 ms executar
<unnamed>: select A, B
from C join D
on C.id = D.c_id

And so on.

It's not possible to change the application (hours of testing after
changes will not be feasible for 2 million LOC).

How can I tell PostgreSQL that it should remove the line breaks (and
change them into whitespace character) from SQL statements? Or there is
an "regexp" I can use for this purpose?

Thanks,

Edson