Date Formatting for dd/mm/yyyy

Hi all.
I am using Postgres 8.3 with Windows XP Pro.
System date format is dd/MM/yyyy

Having problems when I writing records to a database with a single
'date' type field.

e.g. FieldByName('Date').ASString:='2/2/2003'

When the row is viewed in pgAdmin it is always 1899-12-30

I have tried changing the datestyle in postgresql.conf thus:

datestyle='iso,dmy'
datestyle='dmy'
datestyle='ymd'
datestyle='European'

also

lc_time= 'English_Australia.1252'

(obviously stopping and starting Server)

Nothing seems to make any difference.
Who has got an answer to this.

Also thanks to Craig Ringer and others for answering my earlier
questions, it greatly helped me get up and running with postgres.