is there any error for my postgresql installation?

I have just installed postgresql 8.3 on my debian sid, and have set
the password of both system user postgres and database user to the
same password, but when i connect to it using pgadmin3(from the local
machine), i got the error:
--------------
An error has occurred:
Error connecting to the server: FATAL: password authentication failed
for user "postgres"
----------------
how can i fix it so that i can get pgadmin work?

here is my pg_hda.conf
------------------------
# Database administrative login by UNIX sockets
local all postgres ident sameuser

# TYPE DATABASE USER CIDR-ADDRESS METHOD

# "local" is for Unix domain socket connections only
local all all ident sameuser
# IPv4 local connections:
host all all 127.0.0.1/32 md5
# IPv6 local connections:
host all all ::1/128 md5
-----------------------

here is the log messages
-----------------------
2008-12-06 12:33:08 HKT LOG: could not load root certificate file
"root.crt": no SSL error reported (1)
2008-12-06 12:33:08 HKT DETAIL: Will not verify client certificates. (2)
2008-12-06 12:33:08 HKT LOG: could not create IPv6 socket: Address
family not supported by protocol (3)
2008-12-06 12:33:09 HKT LOG: database system was shut down at
2008-12-06 12:32:18 HKT
2008-12-06 12:33:09 HKT LOG: autovacuum launcher started
2008-12-06 12:33:09 HKT LOG: database system is ready to accept connections
2008-12-06 12:33:09 HKT LOG: incomplete startup packet (4)
--------------------------
is (1) a error? what should i do?
what does (2) mean? is it normal?
is (3) ok?
is (4) a error? what should i do?

thanks

--
I'm a web developer using debian+mono(C#)+postgresql+xhtml+js+xsl+xml+css