The following bug has been logged online:
Bug reference: 2046
Logged by: Chris
Email address: termi(at)wp(dot)pl
PostgreSQL version: 8.0
Operating system: Windows
Description: defective date_trunc
Details:
Postgresql 8.0
select date_trunc('week',TO_DATE('2005-01-01','yyyy-mm-dd'))
result
"2006-01-02 00:00:00+01"