The following bug has been logged online:

Bug reference: 2154
Logged by: Glauco Carlos Silva
Email address: glauco.gcs (AT) sercomtel (DOT) com.br
PostgreSQL version: 8.0.3
Operating system: Windows XP
Description: conversion problem
Details:

the result of function (select lower('ÇÁÃÂ')) is ÇÁÃÂ "the expected
result is çáãâ"

and the result of function (select upper('çáãâ')) is çáãâ "the
expected result is ÇÁÃÂ"

PS under the LINUX to

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