Problem with pg_hba.conf

All,

I am having trouble doing db authentication with 'pg_hba.conf' file..

I have added two users using 'CREATE USER' command for a db. And then I have
created two separated password file to do authentication to two different db
in the system.

Also, I have added separate lines in 'pg_hba.conf' file for two db as
follows:

local   db1                      crypt    file1.dat
local   db2                      crypt    file2.dat

But problem is I can connect to both db using both password. What I supposed
to get is, I can connect to 'db1' only with username in 'file1.dat' and
'db2' with username in 'file2.dat'. But that is not happening!!!

Can anybody give some suggestions on this??

Thanks in advance..

Niral